I am 19 years old. I went on a europe tour for 21 days in the end of june. Since then I haven't had my periods. I frequently keep getting crams like I used to have before periods. I haven't had any physical interaction so there is no scope of pregnancy. The last period cycle that I've had was 19-27 june Also, I've gained 10 kgs weight in the last 4-5 months and my sleep cycle has also been affected.