This is probably a nooby question so I will ask it here. I have been vaping on a watermelon flavor the last few days. I have noticed it has lost it's flavor. I go back to my tobacco flavor I vaped last week and it is stronger than I remember. I sat the watermelon down for a day and came back (still in the same tank/clearomizer/whatever it is and the flavor is back full force! Is this normal?