Nope. Not possible.
Chances are the worrying thought of it all made you sick. Stress and worry can do intresting things to you body.
You will hear this all the time and I am sure you think this your self, btu if you are going to be sexually active go on the pill or buy some condoms yourself and make sure he uses them.
Even if he says he didnt cum you cant trust that, many a time my other half has been not 100% sure that he has or hasnt been.. Depending on how pasionate we have been!
Even precum can get you pregnant so be careful peanut as you are obviously not wanting this.