Stopped depo - still bleeding

I was due to get another shot on the 17th of May but didn’t as we wanted to start TTC in the next year (I know it can take 6-18 months for fertility to return then up to year to fall pregnant). However my bleeding seems to get worse and worse.

I had light bleeding from 14th of May for a week. Had just over a week off. Then on the 30th, I started bleeding light and it’s slowly increased. Im bleeding really heavy with big clots, having to get up and change during the night.

It happened the last time but all they could offer was another shot - took it cause it was so bad - the bleeding stopped pretty much instantly.

When should I go back to see if they could do anything for me? I’ve seen a few posts of people saying they bleed for a month and then they didn’t have anything for a few months.