I've left a message for my Dr and am awaiting a call back...

Since late last week my stomach has been bothering me. Alternating between constipation and diarrhea. Haven't gone in 2 days and now today I have a really sour stomach, diarrhea, stomach cramps, and just an overall sick feeling. I haven't been able to sleep in 3 nights because of contractions (I believe Braxton hicks) and belly upset. Saw my OB on Tuesday and she said it may be a bug going around but I'm not getting any better. Thoughts?? Should I go to the ER to be checked. Not really sure what to do. Oh, and I have developed PVC's (abnormal heart rythym) since being pregnant and it is particularly bad today. BP is normal and HB was up at 96. I'll be 27 weeks on Saturday.