Best laxative for pregnant women?

I'm having some major issues with constipation since I've been about 9 weeks along. I bought collace the stool softener and some milk of magnesia because my doctor said not to use any stimulant laxatives because it can cause contractions.

Have any of you had any success using either product? I'm very sensitive to medications so I took half a teaspoon on the milk of magnesia and will take half teaspoon doses a few times a day until it works because Im scared of getting stomach cramps.

Has anyone used Collace and a laxative at the same time? I took Collace 2 days ago and took my first laxative dose today