What Causes Lower Abdominal Pain While On Medication For H.pylori Infection?

Hello,
I've had left lower abdominal pain radiating to lower back and groin for 2-3 months. Blood test all clear, pelvic and abdo ultrasound showed nothing but excess gas on left side of abdo (exactly where pain was). Stool sample has since shown h.pylori positive so I'm currently on day 5 of 7 antibiotics (Clarithromycin, Amoxicillin and Lansoprazole) originally stated on Omeprazole but changed as it made me have palpitations.
I still have the same pains though, no improvement at all. Still on and off daily hard stools too. When will I feel better? Could I have gastritis as well??
Am fed up and want to feel well again!!