Ive noticed during sex the condom tends to unroll, is this normal? For instance i will be having sex for 5-10 minutes or sooner, and i will check the condom, or maybe pull out and switch positions and i noticed it has unrolled a bit. It unrolls enough to the point where like half an inch or an inch is hanging off, why is this?

I know it isnt the size of the condom because the condom is so damn tight it leaves a little red ring around my base when i take it off. Its happened with Trojan and Lifestyles which are pretty much all i use.