Spitting or Acid reflux?!?!

My first trimester was not my favorite. My appetite was lost in thin air, morning sickness took over my body for 4months and I thought things would not get better. Given I didn't find out I was pregnant until March, I never really had heartburn. Now, at 22wks I have a bad habit of spitting(I know it's gross), however, I do not get heartburn. With the school year coming up I wanted to know if anyone else has this problem and remedies that may help. I do not want to be teaching my students with a spit cup in my hand.