Cramping even after cycle and I'm having nausea and major headaches

I Usally Cime On My Cycle On The 5th But August My Cycle Came On The 30th Of September And I Dont Cramp When Im On My Cycle I Stayed On 31/2 Days You Can Say And I Started Cramping Some Days Before And My Period Been Gone But Im Still Cramping And I Feel Very Nausea And Light Headed All Through The Day On And Off And These Major Headaches And My Butt Hurts Real Bad Can Someone Help Me