infusion when ferritin at > 30 or > 40?

hi all, asking if anyone has gotten an infusion at higher ferritin values and what your experiences were.

some backstory: 27F, I have been struggling with symptoms of anemia since March (ferritin was 22, hemoglobin 11.4 g/dl). fatigue, incredible muscle weakness (feels like walking through heavy mud every day), palpitations, breathlessness, dizziness... currently at ferritin 46 and hemoglobin 12.25 g/dl, have been around these values (sometimes higher sometimes lower) since around April/May. have been taking ferrous fumarate 200mg every other day, and I tolerate it okayish (it gives me quite severe nausea and I lost quite some weight due to this, but oh well). despite the improvements on paper, I cannot say I am functioning. I still have debilitating fatigue and muscle weakness, barely able to get through the day at uni (PhD student), cannot even dream about doing sports, etc. etc.

needless to say, my doctors gave a firm no when I even alluded to the idea of getting an infusion (they think I am cured). I do also understand that patients with more severe situations should be prioritized. however, I am in the fortunate position where I have an option to travel and get an infusion privately, and I have found a clinic who are willing to do this for someone with my values and history (in their opinion I am not showing an adequate response to oral iron). it is on the high end of what I am comfortable paying, but I am just so desperate to feel better. so my question is if anyone has been in a similar situation and has gotten an infusion and what your experiences were? or is there anything else you would try before going down the infusion route?

p.s., celiac has been ruled out, and I do not menstruate due to my hormonal IUD, and I have no other deficiencies. so I would hope that if I get my values up, they would stay that way!