Whats wrong with my ankle?

My left ankle hurts and it feels like i sprained it but I don't remember doing any thing. I dont know if this has to do with anything but i have sprained this ankle before awhile back. it hasnt really healed right. just yesturday it started hurting a little part around the ankle and now its hurting everywhere around my left ankle. what could it be? could it be a sprained ankle? could it be my bones? am i lacking any nutrition? It doesnt look swollen but i can feel my muscle being very tight and swollen inside. is there any medicine that i can take atm for the pain because im pregnant? WHAT SHOULD I DO?