There are many variables I bet that could attribute to this. I myself had stomach issues with gambit from 5 pawns about a year ago (5 mins vaping it and always sent me to the nearest toilet). I put it away and came back to it recently and absolutely love it. I guess my experience doesn't really give a solid answer, but it could be your body getting used to something new, could be the juice needs to mellow a bit more, could be something in it you shouldn't have (like an allergy), or it could be unrelated to vaping and you need medical assistance. I think the best option would be to go with what you think is best.
TL;DR
I would put the flavor away, but you do what you think is best for you
