Now that you mention it, I realize I passed 500 posts (a bit ago) - so I'm 1/3 of the way to the Gold - and I just joined on 8/31!
Smurfyy, you may or may not be right - it's impossible for any of us to know. But many of us have been there - I've been there
many times. All I can offer is to take her to a nice restaurant for dinner and have a REAL heart-to-heart talk about things - where they are and where they are going. Maybe you're worrying over nothing. Then again, you may have cause for concern - but in either case, it's better to know than to wonder about it.
Maybe she has the same concerns and talking it out will give you both a fresh new start and increase the bond between you. Maybe something was said or done and was misunderstood or taken the wrong way and a good discussion can bring it out in the open and clarify things for both of you. In any event, a nice date starting with a fancy dinner - perhaps your favorite restaurant together or someplace you've never been but need to get dressed up for (not a movie where you can't talk, but afterwards someplace where you can continue to talk - I don't know, the park, a bench next to a nice lake, in the car on "lover's lane" or a ride in a cart pulled by a pony or close the restaurant down or whatever) is great on its own and if you can really open up to each other (
you need to take the first step here since you want to make sure the tone and openness is shown to her so she feels comfortable reciprocating) this could be a wonderful step forward.
At worst, if you're right and you discover you have fallen apart and even this doesn't patch things up, you can still remain friends even if it's destined to not get much further than that any more - or it could end worse than that too so be prepared. If that's the case, it'll hurt a LOT for a while - you'll blame yourself for your shortcomings or all the things you should have done but didn't do that might have made a difference - but in the end you were just being you and if that wasn't enough then it may not have been meant to be or would have just prolonged the inevitable a bit longer. In time, you'll get over it (we all did even though when it happened we thought we'd missed out on the best thing in our lives and even felt like we'd be better off dead) - I know you don't believe that now (I didn't any of those times either), but it's true. You'll find someone else who seems even better and wonder why you were ever concerned about the former mate. And maybe it will happen again or maybe this will be the one you eventually settle with for the rest of your life - you never know. The important thing is to be yourself since eventually you will be yourself and then if a bond forms, you'll know it is real because she likes you for who you are (and not someone you pretend to be to try to be more convincing at first). Become good or best friends and then let things take their course from there.
Heck, I'm no expert in these things though I've been though them several times. Some ended nice and we remained friends (and still are - 30-35 years later). Some ended very badly and abruptly and if we never see each other again it'll be just fine with me. Some were somewhere between those two extremes. Some lasted only a couple of weeks or less and some lasted for even a couple of years - but the ending never felt good no matter the time (and felt worse with some short ones than it did with some of the long ones).
But eventually I found my wife (during college) and we dated off and on (but remained best friends even when dating others between times we dated each other). Then eventually at a point where neither of us were involved I asked her to marry me and she accepted and we've been happily married now for 20 years (after off and on dating for a little over
10 years). I think the key for us anyway is that we were best friends first and husband/wife second.
Anyway, as I said, I'm no expert in these matters by any means. I've made more than my fair share of mistakes. I can only speak from what I've learned and wish I'd known when I was your age (but I wouldn't have believed it even if I could go back in time and say these things to myself back then). I think I would have done things differently - and in the process, simply made different mistakes instead of the ones I made or ended up in different affairs that also would have ended in the same various ways until I finally found the right person.
There I go again with another long post. LOL! In short, have a heart-to-heart discussion and get everything out in the open and see where things stand and then decide where you both go from there. Good or bad, at least you'll both know (or maybe end up more confused than before). Anyway, that's what a 54-year-old, 20-year-married man suggests (and it's almost certainly different than what I'd have suggested at your age which I frankly don't know now what that would have been).
Best wishes and I hope things turn out for the best.