Endometrium thickness 4mm associated with light and short periods?

Hi ladies! I was looking through my app for my drs office this morning and came across a ultrasound result from when they checked to make sure my IUD was in place before removing it and they had measured my ovaries and endometrium thickness. My thickness was 4mm, from what I googled, my understanding that’s a little low🤷🏽‍♀️ Could that by why my periods are so light and short? Also my left ovary is slightly bigger than my right and I cramp way more on my left. Anyone have any experience with this?