Severe constipation *have tried everything !

Ni
I've suffered from constipation and hemorrhoids since I found out I was pregnant. I'm now 34 weeks and am having really bad abdominal pain and keep trying to go and can't. Needless to say i now have such bad hemorrhoids I can't even walk from the pushing yet I keep having the urge to go and can't. I've drank tons of water , upped my fiber, take colace everyday, take miralax and milk of magnesia.... Nothing has worked or helped this entire pregnancy and now I'm at the point I want to go to the er. Has anyone's dr told them to try something other than I mentioned above? I'm dying here... 
UPDATE:
Thank you everyone for your advice! I'm seriously going to try it all!