Anus 9/10 pain, hurts to poop, stand and sit on hard surfaces, almost feels like muscle is strained or cramping up. hem or fissure? or something else?

Can't tell 4 sure : It might be all of them, however a fissure can cause the severe pain, at any rate you need to be examined, no help online, kindly go to urgent care or ER , mean while sitz bath can help, good luck

Agree with Dr. H: It is not feasible to provide a meaningful opinion without additional history, physical examination and may be some tests. However, you should try to keep your stool soft by taking a stool softener, or fiber and enough water so that your urine is mostly colorless.