Toddler gagging himself

My son is 2 years and all today he's been trying to make himself throw up. He's been gaggin himself with his fingers, hand, food, pretty much anything he can get a hold up. He was starting to worry me, I thought he something was really wrong as maybe something is stuck. I checked his mouth but there's nothing. My mom thinks it's a new sensation so that's why he's doing it. If it doesn't stop I'm thinking about taking him to the doctor. Has any other mom exprienced this with their toddler?