Loss of appetite (I easily get full)

Feb 13 I started being active in sex for the first time p until now, I dont know if it has any relations to what Im feeling, so when I had my period I used diff. napkin and I guess I had rashes, we still has sex after then it started to get super itchy until my next period which was just last week, I had rashes again in my private part but its not that itchy anymore. SO the real problem is this, last 3 weeks ago I was really sick for 2 days with a 38.6 temprature, since then I lost my appetite I was having symptoms of headache, colds, flu, I thought I had clamydia but i guess not, and last week I thought I had mumps since I hav4e symptomps of mumps, they gave me anti inflamation meds. so I was ok until now but I still have loss of appetite, because when I eat I feel full easily, and I wasnt like this before, Im female and im 18 please help