Mind-Crippling Pregnancy Fears 😔

Megan
I need to get something off my chest. I'm extremely scared of pregnancy. To the point where it's almost ridiculous. I haven't done anything but manual and oral sex for two months and I still continue to worry I'm pregnant. 
I'm on the combined pill and I have been for nine months now. I've never missed a pill, my boyfriend and I never had unprotected sex. We always use condoms and the pull out method along with the pill. 
I've never missed a "period" on the pill either. I'm deathly afraid of pregnancy and it's ruining my happiness. We haven't done anything sexual this month after my last period, and I got some spotting a few days ago that lasted about a minute. I freaked out and instantly thought implantation bleeding. I've been pretty dry down there and just feeling awful all month which I realize this stuff can happen on the pill, but I still worry about pregnancy. I've even gone as far as to worrying about there being Sperm on toilet seats or walls that somehow got me pregnant this month. 
I don't know what to do. I've talked to my boyfriend about this several times and it's making him pretty upset and worried about me. Before my placebo week I always get scared I'm not going to get my period. 
What do I do? Any advice? It's really getting to me 😞I worry about any inconsistency my body has during the month and every little thing I automatically think about being pregnant.