Overmedicated for Hashimoto and suddenly gaining weight?

Hi all, I was diagnosed a year and a half ago right before a major move with Hashimotos. my main symptoms were exhaustion, muscle soreness, headaches/ nausea. I never had weight gain - I maintained my consistent exercise regimen despite feeling like I was dragging myself. I was I tially put on 100mcg of levo. fast forward nearly a year and I finally got to a doctor in our new home. I was being overmedicated, so my dosage was dropped to 88mcg and 5 mcg liothyroxine because I still felt tired in the mornings. blood work after 6 weeks showed I was still overmedicated, TSH around 0.3. im now on 75mcg levo. Before my last bloodwork (around 6 weeks ago), I noticed each day the scale going up 0.5-1lb a day. my husband thought I was losing it, but since I work in the fitness industry I am very aware of how my body is looking and feeling and what is normal for me. after going to my doctor and receiving the new 75 dosage, I was told it could be interstitial fluid from being overmedicated and fluid retention. I notice that’s Im bloated always around my lower abdominals- doesn’t matter time of day or before/ after meals. i didn’t raise my caloric input nor change my exercise regimen. I’m now up 7 lbs and I’m scared it’ll keep rising. when I was overmedicated before this didn’t happen. my vitamins and other hormones were tested- everything was nomRNA, slight vitamin D deficiency which I also had before without the weight gain. has this happened to anyone? what can I do?