What cause sereve pain in the back of your leg upper middle of the tigh?

Ineed advice! its importantokay so.. i made a bad choice at school and was sent to an alternative i go back to my home school at the end of the month ..and i'm seriously scared to go back because i know people have been talking about me behind my back calling me names.. and when i walk into first block everyone is going to stare and start talking about i've lost friends and i'm alone.. the whole school now thinks i'm something that i'm i don't know what to do when i get back or how i'm even going to survive the first day. i want people to leave me alone but i know they won't.. anyone have advise? i really need it.. ime getting terrible anxiety from me thinking about all this stuff

Explain what you know about the cause of mental illnesses.

Why do you need two different circuits of blood vessels in your body?