Ugh, sorry to hear about the back up. Here is a quick home remedy for constipation--- drink a cup of grape juice for the next few days. My son has had severe constipation and was even once in the emergency room for what was like a bowel blockage but his own feces (sorry, I know that's gross). Poor guy. Anyway, after the enema (insert smiley face with big bulging eyes)--- they recommended the 1 cup of grape juice daily. Works pretty well. BUT, I know you have the added scare of being pregnant.
Now, any time we have rectal bleeding, that is something we should run by your doctor. I would call your ob and tell them. It's likely just a push injury from getting the bm out and fine but you want to make sure.
And they can offer more solutions for constipation should this be a trend for you. Let us know what happens, okay?
I had to use stool softeners my entire pregnancy bc I was constipated pretty much from day one. Please see your Dr about the bleeding and they can prescribe a laxative or stool softener if need be