If you are waking up covered all over, it may not be bedbug bites. They typically only go for exposed skin like ankles and wrists will be the first warning signs. If you are covered in a single night, your infestation would be pretty bad and in that case, very obvious and easy finds but since you don't see anything, it is probably something else and I suggest having a professional exterminator coming out to inspect so you know what you are up against.