Is it normal for a thirteen year old not to bleed much during the first time having sex?

Possibly. Penile vaginal sex does not have to cause bleeding. The bleeding attributed to "fist time sex" is usually due to an intact hymen being torn. Some girls have a stretched hymen, absence of a significant hymen or for other reasons do not have a problem with penetration of the penis causing bleeding. If you are 13 and sexually active, i trust you are being responsible with your very young sexuality.