I am in agony. What should i do?

Try applying some ice but wrap it up first not applying it direct. It is most likely a pile or an abscess. Local anaesthetic could take the edge off pile pain(I'm uming you won't have that) but you need to take paracetamol and or brufen uming you have no problems taking these medications. Ride it out till morning or NHS 24 phone number is 08454242424.