hi, I have been having intestinal cramping some bleeding in my anus, occasional fever, nausea, and occasional persistent diariah, these usually all happen in flashes/episodes at a time, where I can be going about my day and then I suddenly get this lower intestinal cramping, and back pain. after words I will be really tired and I have noticed blood sometimes in the toilet or on the toilet paper, can you please tell me what is going on with my body?