Help! Do I have bed bugs?

Last night I took a nap on a public park bench. I live in Savannah, Georgia and we have a lot of mosquitoes. However, I went home and didn't feel itchy on my arms or anything. When I woke up in the morning I felt fine too. I took a mid-morning nap and woke up with over 55 welts all over my arms (more so on the left arm). They look like mosquito bites, but what's freaking me out is that they weren't there earlier. I examined my mattress, put my sheets in the drier, I don't see any evidence of bed bugs. Would it take that long to start noticing mosquito bites? THAT many of them? Or could I have gotten bites from bed bugs that were in public? Because it was night time.