Ex-vegan woman lost period - help!

Dear women in this group (sorry guys this may not interest you or be relevant for you :))

I'm a 33yo F who stopped being vegan at the start of this year (see my ayahuasca post for the reason why) and my period has been missing since late September of last year. At that time I had already been vegan for 11 years. My periods used to be pretty regular but light, they just kept getting lighter and lighter, and were spaced out like 40 days instead of the classic 28 days. I've already lost my period in the past like 6 years ago (while I was vegan) but I got it back quite quickly after supplementing with iodine, zinc and selenium. This time I've lost it even though I was eating more, lots of supplements, and had reduced exercise.

I'm supposed to get my oocytes extracted to preserve my fertility in less than 2 months. But the doctor told me that the hormonal treatment can only begin after I've had my period. Except I still haven't had it, despite her putting me on a 10-day Duphaston treatment which is supposed to induce periods. She was VERY sure that it would start any day, but it never came.

My BMI is 20. I eat over 2000 calories a day, and now eat meat, eggs, dairy, fruits and veggies every day. But most of my calories are coming from animal products. I prioritize walking and stretching over running and high intensity workouts. I get enough sleep, and don't feel that stressed out. I am resting a lot.

Have any of you here been in this situation before? And how long could it take for my period to return? I'm assuming that 4 weeks is quite little time for my body to heal after YEARS of being malnourished as a vegan :'( I just feel incredibly desperate and sad and worry that I may have f*cked up my body and my fertility long term. Any words of wisdom or support are welcome...