I Got About An Inch Area Where A Clear Sticky

I got about an inch area where a clear sticky liquid is oozing from my head there is no redness or bump though. It is painful in the area where the oozing seems to be coming from. I do not remember hitting my head or anything. But I was out in the sun yesterday for a long period of time w/o a hat or anything covering my scalp/head. What should I do