HI Cara. I hear you. It can be so frustrating to feel like you did something to make matters worse. I have a very unique experience with iron infusions. I have had many throughout my Crohn's journey.
Ultimately I came to the conclusion that they aren't for me. Not to discourage you at all because we all react differently. But in my case, I would get ill afterwards. And sometimes immediately after or during the infusion. Stomach ache, nausea, bad fatigue. Just overall feeling of feeling off and ill. I would even throw up sometimes.
So, just letting you know you aren't alone in feeling these symptoms. I would suggest resting as much as you can and taking it easy. Perhaps in a couple of days your body will process the load and you will feel better.
Sorry you are feeling badly.
Hugs, Elizabeth (team member)