What causes random onset dizziness and stomach pains. I've also been belching a lot. Also have random headaches on one side. Hospital said vertigo?

Need more testing. I suggest seeing your primary care doctor for further work-up. Without knowing what tests you had already, it is just hard to tell what is going on.
I ADVISE YOU TOO. See your family doctor within the next month.. Most likely causes: 1.Migraine syndrome 2.Heartburn something serious ? :.