I have a pill, mostly rectangular in shape, imprint on one side is 79, and on the other side is 3. it is supposed to be for Zolpidem 10 mg, generic for Ambien 10 mg. But all the other prescriptions I've filled for zolpidem is a round tablet with different markings on it. Can anyone tell me if this has changed, or if I got a different pill by mistake. Thank you very much