Q&A: Is it normal to be 1cm dilated at 30 weeks pregnant?

I am 30 weeks pregnant with my first baby. On Sunday afternoon, my husband and I went on a fairly strenuous four-mile hike. Afterwards, we ran some errands, cooked dinner, ...etc., and I didn't realize that I hadn't drunk much water. Later that day I experienced nausea and developed a stomach ache so awful that I doubled over in pain. My husband took me to the hospital where they hooked me up to a monitor and re-hydrated me. The baby is fine, but the monitor showed that I was having contractions every three minutes. The hydration improved my stomach ache, but did not stop the contractions (which I couldn’t even feel).

After two shots, my uterus finally settled down. They checked my cervix, and it was 1 cm. dilated, but they said it was "very hard." A few hours later, they sent me home and told me to take it easy and get an appointment with my doctor later this week.

Since then, I have really been taking it easy. I am feeling a lot of contractions, but I am pretty sure they are Braxton Hicks. What I felt in the hospital was a stomach ache that felt more like menstrual cramps, and now it's a painless hardening of the uterus with no real "schedule." I am very nervous because I am only 30 weeks along. I’m wondering if it is at all normal to dilate this early and feel lots of Braxton Hicks contractions. Is there still a good chance that I will make it to term?