Is pregnancy possible?

Let me start off by saying I'm a BERY anxious person when it comes to anything sexual. Let me also do I'm 20 years old and have taken all my health classes and I know how condoms and birth control work, to this question is my anxiety talking. Please no ignorant comments... I haven't had sex since October. But since around the summer time I've been stressed about becoming pregnant. All that my boyfriend and I have done recently is the basic hand/oral. Anyway, I'm always convinced I'm somehow going to fall pregnant in crazy situations. If he gets precum on my clothes, his hands, etc. last month my period was a lot shorter and lighter than usual. It started Jan 26. Yesterday feb 14 I took a pregnancy test and it was negative. Can I assume I'm fine? ( I started birth control this month, so I know that wasn't the cause of light period) was it caused by all the anxiety I put myself through? My cramps were slightly worse as well. I haven't had sex since October but I can't stop freaking out