OMG, I'm having the same problem and its making me really miserable. I have days where I cramp really bad, but I go to the Dr. tomorrow for my monthly check up so I will see if my Dr. can prescribe me something.
I started getting constipation very early in pregancy too it got so bad that i wouldnt be able to go for 2 weeks. When i switched to a high risk dr they told me to take miralax daily. For me it worked in a couple hrs when mixed in a glass of orange juice (you cant even taste it) and i had relief. I think its amazing because i was miserable.
Try a daily stool softner. I take iron pills and its definitely giving me some troubles but i started on collace daily to try and help regulate things. Talk to ur dr if its so bad ur straining all the time and bleeding
Constipation is a common aliment of pregnancy. It's due to hormones. Along with water, increase your fiber intake. I eat about 7-14 prunes at night then eat a bowl of frosted mini wheats in the morning and I go. Check labels for how much fiber is in what you're eating. Fruits and vegetables can help also. If you still can't find relief, milk of magnesia is safe to take during pregnancy.