Gaining weight?

I’ve lost 110lbs so far. I’m on 15mg. I’ve gained 8 freaking pounds in the last 2 weeks. WTH is going on?!?! I’m tracking calories. I’m drinking water. This week I’ve skipped the gym bc I’m sick, but before this week I go 5-6 days a week doing cardio and strength training. I’m not on or about to be on my period. Anyone have a weird time where they gained and if so, how’d you stop it? I’ve plateaued plenty, but never gaining. I hate this. I was so hoping to see the 160’s by the new year but this morning I was 182 again. It took forever to get into the 170’s, I don’t want it to take forever to get back to them.