Vortoxitine and anxiety getting worse

Hi. So I've been taking Vortioxetine for some months. I started on 5mgs for a while which was okay but then my anxiety broke through. it was put upto 10mgs about 8 weeks ago. I would say week 6 was a good week. i felt quite positive. Week 7 was not good. Then I had a couple of good days but I have now gone back to having bad anxiety. I have had a bad back which hasn't helped but that has improved. I start to feel very odd and then get a surge of anxiety. It's awful. My doctor was going to put dose upto 15mgs but we thought we would wait to see if things got better. Not sure what to do. I know these tablets take a while to work but would have expected to feel better than this by now. Has anybody experienced this at this late stage?