I found this best answer so far:
Maybe, as you probably know that the tests pick up a pregnancy hormone which reads positive, sounds like you may have, but im no expert. Doubt its happened before unless your tests have read positive? Dont worry about the clinic, they looked at me like that too! When i miscarried though i did have bad cramps. Keep your chin up, dont stress, relax & let your body do it naturally. Its a blip, you'll be fine.