Hi I am 15 and I am scared because I missed my period and its been a month and a half and I'm scared to speak to my mom and I have no symptoms of pregnancy but I haven't been able to use the bathroom regularly

Have you had sex ??

If pregnancy is a possibility, you will need to take a pregnancy test. You can purchase one at most supermarkets. Follow the directions carefully. If you are pregnant, obviously you will need to get over your fear and speak to your mom. If you aren't pregnant, it is likely just your age... periods can sometimes be off here and there in the teen years.

Since it appears that you are sexually active, it would be wise to think of your life right now, and your future, and discontinue any further sexual activity until you are of an age and situation in your life where 1) you would be emotionally prepared for the possibility of having a child 2) you would avoid the increased risks in pregnancy at a young age 3) you would be financially in a better position to raise a child and 4) you would be mature enough to be able talk to your mother

You don't have to continue having sex just because you have already done so in the past.

Assuming you had sex, there is not a lot of signs this early, except missing your period.
So you buy a test and use it first thing in the morning as soon as you wake up.

Also things like infections and other illness can cause it