Im 20 but I feel 12

I had dry sex a while ago (he was wearing nothing but I had jeans and panties on the whole time and he ejaculated on my clothes we didn't have direct gential contact because I was clothed) and since then I've had 6 periods. I went to a gyno appointment and said I looked normal. I can be sure I'm not pregnant right?
I'm home schooled and have been raised in a very strict, Catholic household and my mom told me that God would punish me If I did anything sexual. Even if I didn't have sex, he would punish me by making me pregnant.
Thanks ladies.