So irregular period TTC

Help..!!! Iam having and suffering from a very irregular period since 2-3years ago. My month cycle is very short...i could've up to 15 days of period and stop for 2-3 weeks and starts again for another 10-15 days...for info i am actually ttc for a first child at this age of 41...i know its a bit too late but i had a rough and bad younger days...i've had 2 terminations and 1 ectopic during the age of 30-35...pls dont judge me as i know my history and young age is ruined...but i have a lovely husband who understands me and i wanted so much to start a family  with him but with this problem im having bow it seems impossible... I specially now i've my period for straight 20 days but light flow and sometimes just a thin bright red bleeding...pls help..!! I dont know what else to do since i went o gynae couple of time and did pap smear and  cervical scanning / ultrasound .. It all came back negatives..😪😪😪😪😪😪