My sunburns getting worse! help?

I have a sunburn and i keep going to the pool with a shirt on because the sunburn is on my shoulders. i have heard many many things like caffine will help and deodorant and aloe but i want an ACTUAL real thing that will work! does anyone know what will make my sunburn go away until this saturday? because i have a barbecue and my shoulders hurt so bad i can hardly wear a shirt! please help me!