I dont know if anyone has ever died of an ankle injury - so the worst case is ull live in pain - until somethin else kills u - old age, a naggin wife, stupidity, u name it.
Since u say it only hurts when u walk another option would be.. well not to - ever. We talkin worst case here so hang on.
Ive sprained my ankle and got better in about a week or so. Then again I wasnt paranoid coz I knew it wasnt anything major. Now since you have started posts askin for suggestions im thinkin your case is pretty bad. Dude even if u have a freakin warrant on your name as long as they dont have ur pics hangin on  hospital walls u should be fine. Goto the ER and exaggerate your pain like you are about to die any second. Any public or private hospital MUST TREAT U. Its the LAW! No exceptions!
I dont like payin bills of any kind. If ur like me tell em ur name is Rajesh Hamal/Shiva Shrestha/Denny Denzokpa whatever. Hell if u dont wanna talk act dumb and point your finger at your ankle. Use hand gestures accordingly to get your point through.
U can fix a broken/sprained ankle but u just cant fix stupid! Dont be one - get some medical help. N if ur just paranoid about something that isnt major - give mom a call. Ull feel better already.