Bedbugs are small, oval insects that feed by sucking blood from humans or animals. They often infest beds in unhygienic homes and hotels and if you find yourself in one of these establishments they can cling to your body and be transmitted to your own bed once you return home. Bed bugs are most active at night and will bite exposed skin while you are sleeping. Small, flat or raised bumps on the skin are the most common signs of a bed bug bite.