Sure you can have sex. As long as you can remain erect and it is not uncomfortable for you not being able to pull it all the way back while having sex, I don't see a problem, but you should work on being able to stretch it back over the gland while erect.
The reason for pulling the foreskin back or as far back as it will go before putting on a condom is that it will then allow free movement of the foreskin. If you put the condom on without first pulling the skin back, you will find that it will restrict movement of the foreskin and you may not experience the full sensation and may run the risk of going soft to early.
So, the key here is to pull the foreskin back after you are erect and then put the condom on.
Last edited by Hoop; 11-09-2003 at 05:04 AM.