It's scary how similar this is to a discussion I had with my therapist recently. Except, I'm 28, and I've had three(!) whole dates. Your concern is basically the exact same concern I have and expressed to her, and while I have a negative opinion of myself in many regards, I am most assuredly not stupid; therefore, I conclude that you are not stupid. At least, not on the basis of having this concern.

Unfortunately, I have no useful advice or anything to provide beyond that assertion. Sorry.