Luteal phase ???? Help

I breastfed for 13mths and had to go on the mini pill as my periods where coming every 2 weeks and lasting 2 weeks. I have ultrasounds etc and all came back ok so the doctor put it down to breastfeeding ( this was around 6 mths so they put me on the pill. Then I stopped breast feeding and went back to normal pill. Now we are trying Tcc out second  and I went of the pill and once again my period came after 17 days.. Not sure if It's my luteal phase or if anyone is in a similar situation it been through it. Will my periods ever go back to normal. 

My daughter is now 16mths and I would of thought they would of sorted them selves out by now