Insecure

So something that’s been worrying me is that I have been with 3 guys and I couldn’t make any of them cum!! Like even after hours of trying! A LT ex bf of mine told me he couldn’t tell the difference between fucking me and rubbing on me and the other two I’ve been with haven’t finished either. I am starting worry because I always see posts abt girls making their partners cum and I honestly feel inadequate because I cannot pleasure my partners. Help?!