Period issues!

Really hoping there is someone here able to offer advice on this. - Im 33. Have 2 children. After birthing my last child 4 years ago, ive been having issues with my cycle. Im lucky if i get 2 weeks off between bleeding now. And each period lasts 6 days then stops for 1 then i begin spotting. Ive had scans. Swabs and even a biopsy earlier this year which was normal. Its getting worse each passing month. Im already on iron pills due to how heavy my periods are. I honestly dont know what to do. I had hormone bloods 2 months ago but again normal. Im not on birth control as on a migraine sufferer and previous breast lump operations so dont want to increase any risk of further issues. Its really getting me down now as im bleeding more than not. This was never an issue after my first child 8 years ago. Just need some advice. Thank you x