How long can you take ppis safely?

I have undergone treatment for h pylori followed by 1 month ppi. After finishing course my stomach symptoms came back on 2 week without medication. Doctor has suggested me to take ppi for 2 more months. I have 3 questions :- 1)could the symptoms at 14 days be acid rebound? Or was the gastritis not healed? My symptoms were burning sensation in stomach whole day, nausea in the morning upon waking up and lots of flatulence and regurgitation. 2)how long can i take ppi safely and whether i should take probiotics and vitamins to supplement deficiencies caused by ppi. 3)ppis have been known to cause kidney damage, b12, c and iron deficiency, deficiency of magnesium, increased risk of salmonella, campylobacter and c diffcle infections so how long can you take them safely.