Post menopause bleeding

I am 53yrs old. After approx 4yrs of suffering horrendous peri-menopause flooding, bloating, anaemia and constipation, I ended up having a hysteroscopy and biopsy which thankfully gave clear results and literally the same month my periods completely stopped - this was approx 18 months ago. I have assumed I'm now in menopause and have been having hot flushes although this has died down over the last month or two. I have not had menopause confirmed by my GP. 
I was horrified to discover I started bleeding again last night and am now really worried as everything I'm reading says it's not normal to bleed after such a long time without a period. Has anyone else experienced this and found it to be normal? I will call my GP this week and ask for a telephone appointment to discuss as we are currently in lockdown?