why is my ear clicking?!

okay so my left ear has been clicking for about 9 months now I have this random clicking in my ear it happens mostly when I swallow so its quiet annoying but sometimes I just forget about it and i DO NT notice it that much but then other times it will be hurting a lot. I went to the doctors and they gave me nose spray I used it and it did nothing. so I went back because it was hurting a lot. He said this may be due to fluid in my ear. He said that it usally goes away in a couple of weeks and has refered my to an other doctor but my appointment is in like three weeks its hurting a lot and was wondering if someone would knew what is causing my ear to click.or does anyone know how to take the pain away. I have did a bit of research and found that it might be an allergie to something but to what some have said it can be to dairy wheat eggs or cituris fruits. How would I know for sure that its a mild allergie to something