Is sudden acid reflux due to possible pregnancy?

I suppose that could be possible.  The hormonal changes during pregnancy can cause acid reflux by decreasing pressure in the LES.  Generally though those kinds of acid reflux problems are more prominent further along in pregnancy.  This is due to the growing baby pushing on your stomach and causing acid reflux. 

There are other reasons for sudden acid reflux like symptoms such as dietary changes, constipation, hpylori infection, gallbladder disease, hernia or other issues aside from pregnancy.  If you have frequent recurring issues with acid reflux talk with your doctor.  Untreated acid reflux can cause damage to your esophagus and can be extremely painful!