I used to drink coke first thing in the morning probably for a whole year, off and on I would stop. Like a month ago I stopped drinking coke first thing in the morning. For lets say three weeks now my tummy hurts like an upset feeling but my mouth don't feel like I want to vomit. Can my issue be caused by drinking coke first thing in the morning for so long?

This is a long shot but caffeine withdrawal is a slight possibility.
This is a discussion of caffeine withdrawal symptoms just for consideration:
CAFFEINE WITHDRAWAL RECOGNIZED AS A DISORDER

Well thanks but the symptom that I am having is not mentioned it this article. Mt belly hurts in a funny way

Maybe there is no connection between the coke and the stomach problem.
Have you discussed the problem with your Dr?

It doesn't sound like there's a connection. It's good you gave up the coke though.

Is there a possibility that you're pregnant? That often causes morning stomach upset.