Hi thanks for your question.
Pain and bleeding after bowel movements could be due to haemorrides.Additioanally you may be having some infective focus in perinal region which is giving you chills
follwed by drop in temperature.I would suggests you to consult a general surgeon
,who may perform proctoscopy/sigmoidoscopy
on you to determine what exactly is cause of this bleeding and pain and ccordingly he may prescribe you drugs or suggest an operation.
Hope this answers your question.