Not sure

I found a bug on a piece of clothing that was lying on the floor that I was about to wash.  It kind of looks like a bed bug, but have no bites and see nothing on the mattress and box springs.  If it is a bed bug, it was an adult.  When I went to kill it, it left a brown stain on the clothing.  Is there a bug that kind of looks like a bed bug, but isn't?  We were traveling a couple of weeks ago and I have looked through my computer case which was close by and have found no evidence of eggs or bed bugs nor have at any time have I noticed any bites.  What do you think?