So confused! Please HELP!!!

I had a d&c on 01/15. I still haven't had a period. I called my doctor a couple weeks ago and she said not to worry because it can take up to 3 months before your cycle gets back on track. Well today I started feeling nauseous and kind of off, so I decided to take a pregnancy test just to see, but not really expecting too much. It came back positive. Am I really pregnant?? or could it just be that my levels haven't fully dropped down to zero yet? I'm so nervous to get too excited... Please, any help or advice is MUCH appreciated!!