Sylvia.. maybe you know the answer to this, or have some advice?

I was told I am anemic (which I knew, but no doctor had ever done anything about it before). My GP prescribed me Ferrous Sulfate- 324mg/ 2x a day. She claims I need a high dose, because my red blood count is at a 9, and that's what it will take to get me back to an 11 (which is what I was at when I first started seeing her). She did tell me to take a stool softener while on the iron, but she didn't say how often? A couple of times I've used one had some not-so-pleasant results. LOL But I'm waking up in the middle of the night in agony. My entire abdomen hurts so bad! It's already messed up from who knows what (I have a scope on the 15th). But this is ridiculous. I read on a website that one should work up to that amount? I'm thinking of cutting down to 1 pill a day.. my stomach is a mess. TMI, but I am "going" probably every other day at the least.. so I'm not sure if I'm experiencing an mild OD effect, constipation, or just that my stomach doesn't care for the dosage? Any advice? I'm drinking plenty of water- well, at least 8 glasses a day, so I'd hope that isn't the problem?