Dead animals will smell until they are completely decomposed or until they are dried out. The damper the site, the longer the odor will last. If a rat dies near a steam pipe, the smell can be horrible for weeks. The odor from a dead mouse may last only a day. In fact, there may be no noticeable odor from a single dead mouse, but several dead mice in the same area could be a problem. A dead rat may smell really bad for a week, but there can be some lingering odor for as long as a month.
Before 3 days when laying down on bed by turning head to left its worst for few seconds then disappeared. Vertigo (Definition) A type of dizziness where the patient inappropriately experiences the perception of motion usually due to a dysfunction of the inner ear apparatus. It can be associated with nausea, vomiting and an unsteady gait.
1 This condition causes an intense and brief but false sense that you're spinning or moving. These episodes are triggered by a rapid change in head movement, such as when you turn over in bed, sit up or experience a blow to the head. BPPV is the most common cause of vertigo.  Infection.