How should I treat these insects/spider bites?

I woke up one morning a few days ago and realized I had these red bumps on my legs and just ignored it until the next morning I had even more. And now I have about 20 of them all varying in sizes on my left leg. I am pretty sure they are spider bites, but nothing to be very worried about. I would just like to know if there are any remedies for these bites, as it is summer and I would love to wear my shorts.

PS-I have already washed all my clothing and changed out my bedsheets.

Here is a photo I found online of what the bites look like. I have one about the same size as in the photo and all the others are smaller.
http://www.romneypestcontrol.com/Gifs/Insects/bite.jpg