"I come way too quickly - is this because I have a small penis?"
I come way too quickly and I am wondering if this is because I am quite undersized in the penis department.
Could there be a link and how do I stop it happening?
Unfortunately, you're right - there is a link. Not only do below average sized men have to grin and bear all those big-is-better jokes, they ejaculate much faster than their larger friends.
All penises have roughly the same number of nerve endings in the head. If your penis is small, they're concentrated over a smaller area that makes you more sensitive and prone to premature ejaculation.
The opposite is true for men with big penises because the nerves are spread over a larger area. Highly unfair, yes, but sadly true.
Help even up the score by masturbating to orgasm before you have sex (just before you see her, for instance).
And don't stop having sex just because you've had an orgasm. Continue to pleasure her using your fingers and tongue until you get a second erection, then try again. You'll usually last longer the second time around.