Is having sex more than once duribg one time ok, or is it traumatic for the girls vagina, and are bacterial infections more prone this way?

OK. As long as it is enjoyable and not traumatic (does not cause pain, bleeding, discharge or other discomfort), you can have sex as many times as your partner is able to accomodate. Bacterial infections will not occur unless your partner is infected with some std and then even one sexual episode can create infection. Enjoy.