I have been taking omeprazole for 12 days (3 days at 40mg then 20mg/day) at first it was wonderful but now my symptoms are worse - should i stop?

Omeprazole 2 x daily: I would recommend taking omeprazole 40 mg daily for the next 10 days followed by ranitidine (zantac) 75 mg twice daily x 10 days. Avoid alcohol and acidic foods x 2 weeks. If your symptoms have not resolved after this, then you should see your primary care doctor for an evaluation. If you have any more concerning symptoms, such as black/ tarry stools, weight loss, or vomiting; then go to the ER