Bleeding Hemorrhoid TMI question?

So I'm 35 weeks. I was put on Nifedipine last week for contractions. It gave me diarrhea and began aggravating my hemorrhoids. I called the doctor and they said there was no substitute medication, and to basically deal with it. Well, I haven't been working because it's just too bad. And now, they're bleeding and won't stop. The hemorrhoid is about the size of my fingertip, and is extremely painful. Is there any way to stop the bleeding on my on, or should I be heading to the ER?