I'm always feel sick and i am never sick,always seem to come on in the afternoons,i know i'm not pregnant and i have had it for a couple of months now?

Keep a diary: of when this happens, what you have eaten each day, what medications or supplemenets/vitamins you may be taking, and take this to your GP when you get an evaluation. Anything that has lasted for months needs an explanation. Oh yes, and get a pregnancy test just before you go, because unless you are a virgin you really can never be sure!