What Type of Bug Is This?

I have found several in my bed, but they are mostly all over my apartment. Some are in the carpet and some are in my bathroom. I moved out of my apartment a couple months ago, but had to leave my furniture there. I have been staying with my parents, but have gone and checked on the apartment. I deep cleaned it when I left, but when I went to get my furniture I found 5 of these on my daughter's bunk bed mattresses, but the apartment is full of them. They are not flat either and they are pretty tiny. I first thought they were bed bugs, but from looking up pics, bed bugs don't have that middle abdomen area.