Aspirin regimen symptoms and conditions

I've been on Ocella -- a generic form of Yasmin -- since late March/early April. I only started taking it because I was on a different birth control pill in another country (no side effects there) and then moved to the US in December and when the other pill ran out (not available in the US) my doctor in the US prescribed Ocella (Yasmin).

About ten days ago I went to the ER -- I discovered I have Supra Vesicular Tachycardia (SVT) -- apparently a condition a person is born with but doesn't discover until their 20s, 30s, later or never.

Then last night I went to the ER because I was having pressure across my chest. They did EKGs, blood work and then even admitted me to the hospital for the night and did a stress test the next day. Everything came back normal, yet the cardiology nurse prescribed (as a precaution??) an aspirin regimen (this would be to prevent stroke, blood clots I suppose) as well as 0.4 nitroglycerin only in case of chest pains. On the discharge papers it says I should go back to the ER if, after three doses of nitro, the pressure does not subside.

I read the medical insert for Ocella tonight. It mentions "pectoral angina" (chest pain) as well as stroke, blood clots, etc. as possible side effects of Ocella. I'm inclined to stop taking it.

I've also had some bowel issues but I don't know whether those might be caused by the pill as well?