Bathroom Question (maybe TMI)

I'm 11 weeks pregnant and have struggled for about 4 of those weeks with constipation. I've been taking milk of magnesia every few days because that is the only thing I've tried that works. 
Well, another problem is that whenever it kicks in, it's always super hard to go. Like, poop is rock hard at first then just diarrhea. But it's always so painful and normally hurts for a day or two. 
Is there anything I can do about that? I haven't seen my doc yet, so I don't know if they'll tell me if stool softener safe ok.