Anxious about pregnancy. HELP

Is it true that you can give your self pregnancy symptoms? 
I have been worried about being possibly pregnant for 20 weeks now. 
Dispute having periods and multiple negative home pregnancy tests.. 
I'm still having symptoms like tingly nipples and bloating, low pelvic pain and aching bones, It also feels like my pulse is a lot faster and when I lay down I can feel pulsing above my belly button. I have just finished my period and I'm on the pill. 
I havnt had sex for month because I have been so anxious about pregnany even though I'm on the pill and my partner always wears condoms. 
So if I'm overthinking pregnancy and stressing out about it do you think I can be giving myself these symptoms because of stress?? 
I have been to the doctors, they said I don't need a blood test because I have had periods