A couple of weeks ago the weather got pretty hot and the pollen count high, and my left upper eye lid swelled big time, I used ointment and allergy tablets and it went down within 2 or 3 days. The weather tailed off and I didn't have a problem for a week, but now it's back up again about 10 days later with the weather back to searing heat again. I'm suspecting this is probably hayfever, however I am 18 and didn't every have hayfever til last summer so I'm not sure.= as to what my hayfever symptoms include yet. What do you reckon? Cheers.

You can develop allergies at any time in your life. Since you can associate it with the weather, you are probably right about it being hayfever or some other sort of allergy. You should go to the dr and get some allergy eyedrops.