Iron is disappearing

Hi. I had gastric bypass November 22, 2016. My 4 month blood work showed my ferritin at a 5. I was sent to hematology, they ordered 4 iron infusions. 1 per week for a month. Ordered a colonoscopy and an endoscopy. On April 26 my primary ran my iron and ferritin. My ferritin was 314(H) and my iron was 155. I met with my hematologist a week ago, exactly a month later. My tests came out fine. Scary part is my ferritin was a 60 and my iron a 55. She is ordering a test of the mid area that I can't remember the name of, and moved my blood work up to the 12th. I asked her to run it sooner because I'm afraid of all the ferritin disappearing and it taking another month to feel better again. I'm having it checked tomorrow. Has this happened to anyone? Any ideas what could be happening? It's ovious something is wrong but other then being weak from anemia I've had no problems at all from day one. Thank you in advance.