Someone help I think I have a blood clot and I'm only 16?

Help there's a weird pain in my left foot like in the squishy part between the back of the foot and the bone in the side. It feels like that feeling you get after you regain circulation. The pain is kinda up my leg and it's definitely not stabbing or anything, just aching. There's no visible difference. Help me I'm 16 and i'm scared! What will happen if I do have one?!