Do you know what kind of bug this is? Is it a flea?

You don't have a picture, so you can't know what you are talking about. This is a photo of a flea. Fleas are small, wingless, jumping parasitic, dark brown or brown. Adults usually live in mammals and a few live in birds. Antennas are thick and short. The mouthparts are sharp and used for sucking. Broad abdomen, developed hind legs and strong. Adults are tiny, about 3 mm long, wingless, hard and flat, parasitic on mammals and birds, with perforated mouthparts and sucking bisexual blood, and can be infected with plague and typhus.