Sunburn!

Ok so my first trip of the summer didn't end well at all. However, It started out great, the first day we just relaxed and took the paddle boat out and stay'ed in the cove area. The second day however we took the paddle boat out again (earlier like 10am since my friend just had to go out early) this time we paddled out of the cove and went to two different islands, then all the way to the marina to swim (over 4miles) the whole trip took a little over 3 hours, and it was around 1pm when we decided to head back. Once we got back we noticed we were a little burnt, we decided it was because we forgot to put on sunscreen. Once we got back to the cabin we both noticed we had red tan lines, and were very burnt. Due to my friend not being able to stand it, we packed up and went home late the night instead of the next day.
Now I'm sore, ITCHY, hot, and burnt. I can't sleep because of the constant itchiness, parts of me are red as a lobster, and I'm constantly burning up. Plus did I mention that I'm ITCHING LIKE CRAZY?!?!?
So what have I learned and what is my advice to you? Always wear sunscreen, even if your the only person who wants it, you use it that way you won't have to go through this agony.