This may make you feel better or worse but it has a lot of useful information. (https://www.medicalnewstoday.com/articles/271647.php)
If and when I bottom I for one am not all that keen on big penises. They hurt and I just don't get that tingly, on-the-spot orgasm. So I was not all that worried about other guys' cocks except to make sure they were not too big. The main thing was whether he tried to please me in some way and I, of course, went out of my way to please him. Hopefully he worked. So, unless it is scientifically too small (and then it appears there are aids for that) look for guys that want to please you as a human and not as a penis.