How To Confirm Pregnancy?

Hello, i was diagnosed with premature ovarian failure a little over a year ago and was put on premphase to control menopause symptoms and to make me still have a cycle every month. I have been having full cycles as expected with the meds until June. May cycle was fine, no cycle in June (which I called my gyn and he said it was normal to have no cycle or just spotting and not to worry), had spotting in july, and no cycle in august. I started feeling funny with nausea about two or three weeks ago in the morning and I even vomited. I took about 4 hpt and they all said positive. I even went to the health dept and they confirmed it. They said I would be due in feb 2012. What I'm worried about is am I really pregnant? My gyn told me I had a slim to none chance of conceiving on my own. Did my ovaries just kick back in which he said COULD happen or is it my medicine or in my mind hat I'm pregnant? Im just worried about a false positive and/or a wrong due date if I am. Thank you for reading and responding!