Teen, Had Unsafe Sex, Missed Periods, Vomiting, Excessive Sleep, Weight Loss, Mood Swings, Negative Pregnancy Test. Suggestion?

My last period end on may fifth. I had sex on may twentyth and the condom fell off. Today is august fifth, that s three months without my period. I feel great some days, others I feel horrible, I feel like I m going to throw up at random times of the day but haven t thrown up once. I feel like I need to sleep for ten or more hours a day, I try to blame it on work. My eating habbits are different now, I haven t ate as much as I used to. I ve actually have lost weight. My moods change easy. My face has been breaking out. I just feel different. I thought I could be pregnant, all the home tests I ve taken came up negative. I haven t been to the doctor because I m only seventeen and my parents refuse to give me my medical card. I m very afraid I might be pregnant and I don t know what to do! Please help me.