Small black bugs shaped like sesame seeds?

I have seen two in the last week, one was on the kitchen counter and one crawled across my laptop. It was the size and shape of a sesame seed and black. I wanted to put it in a bag so I could figure out what it was so I got it onto a piece of paper and it crawled around on it until I got to the kitchen, but then either jumped or flew at me and I lost it. I am thinking either bed bugs or ticks. Neither I nor my roommates have noticed any bites, which I would expect from bedbugs. We have two cats but they don't go outdoors and I live in the city so I don't think ticks are likely. I checked them for ticks and saw none. Are there any other bugs that these might be?