The connection is plausible
The NIDDK lists fizzy drinks among habits that can increase swallowed air and gas symptoms. Eating or drinking quickly, drinking through a straw, and chewing gum can also matter for some people. This does not mean carbonation is the cause of every bloated day.
Try a simple comparison
For a few days, note when you have a fizzy drink, its approximate amount, the meal around it, and any symptoms. Then try a similar routine with a noncarbonated drink. Keep the rest of your day as comparable as you can and see whether a pattern repeats.
Keep the bigger picture
If symptoms are frequent or bothersome, discuss them with a clinician. A beverage swap can be a useful observation, but it cannot rule out other causes.
Sources & further reading
Sources support the health information above. Product descriptions reflect Bye to Bloat features.