Suggest Medication For Headache & Dizziness

In November my period was five weeks late and I was on birth control. I stopped taking and had my period in December but my doctor and I both decided for me to stay off of the pill. Since December my fiance and I have not been using any contraceptive as we are trying to have a baby now. I just finished my period, but it was very different. It lasted 3 days with heavy to medium flow and the next two days I had spotting that was brown in colour and thick. I usually get really bad cramps and this time no cramps at all. I did not even know my period started until I went to the bathroom. Since November I get really bad headaches, get dizzy, feel as though I am going to through up, but never do. I have always been very tiny (110 lbs) and always woke up with a flat stomach, now my stomach is not flat and I get so bloated that I look pregnant. My back has been hurting me and I have been having trouble sleeping. I will be turning 30 next month.