5 months not on period?

hi am_____am 13 years old i came on my preriod when i was 12 this year an decamber i have not been on my period an my mom thinks am doing something like sex but am not that canna girl who would do a thing like that she did not raise me to do things like tha i havent had sex yet am scared.My friend told me it could be because am on the plus size but am to scared to even think about my weight problem please help me before i die of to scarenest even if thats not a word please am beggin you you to help.Because am and school i cant think because i got this on my mine i have to go to a good college an high school so please some give me a answerit would help

5 months not on period?
At your age, it is normal to have irregular periods. Other causes could be your weight - malnutrition - poor diet - exercise. You should consult with a doctor.
Reply:When you are young (teen years) and when you get in your late 40's and 50's - then your period becomes an irregular and unpredictable thing! I wouldn't be too worried about it - but it doesn't hurt to talk to your doctor - to understand the cause. Report It
Reply:If you had not had sex you are fine. It is normal to be irregular when you are young. It doesn't matter what size you are
Reply:Well if you havent had your second one then thats fine. Your "cycle" will be irregular probably for the first two years. Its totally normal.
Reply:It takes some time in order for your cycle and periods to become regular. This can take 1 - 2 years.
Reply:Talk to your doctor ASAP!