Mini Pill advice

I'm 17 years old and I just need some advice, I've been on the progestogen-only pill for 4 months now and it's been terrible. I seem to always be on my period and when I do stop I come back on a couple days to a week later. My periods have become more painful and a lot heavier, last month I rung my gp to try and change my pill they said I can but they advised me to stay on till I hit my 3 month mark at most and it can take 3-4 months for my hormones to settle. I don't know what to do at this point whether I should continue and hope that it does get better or whether just to change and go to a better option but have my hormone scrambled up again.