Thanks for your patience.
Since at 29, there is significant hair thinning, I would recommend the following:-
1. You seem to be having female pattern baldness, which is due to a hormonal cause. Low levels of iron , folate and Vit B12 could have contributed to it.
The level of male hormone , testosterone increases in a female body and causes hair loss. Though your levels of hormones are normal, it would still be possible to have female pattern alopecia as the levels of these hormones may be normal in blood but locally near the hair follicle it may be deranged. Also IUDs can cause hormonal changes which may contribute to the effect on your hair.
It would be best to treat it , so as to prevent further hair loss and also for regrowth of the hair.
In addition, you can apply Rogaine lotion twice a day to the scalp, which will promote hair growth. It is available without a prescription and you can start it from now.
These measures will help to regrow the hair back.
Please let me know if I can address any other concern for you.