Weight Gain After Nuvaring

Last month, after reading several reviews about side effects of Nuvaring -that I was expirencing but had no idea until I read about it- including horrible anxiety, fatigue, loss of sex drive and a few others, I decided to switch to the pill. Within 3 weeks of taking it out, I gained 21 pounds. Right after I took it out and started the pill- I stopped because my husband and I decided we wanted to start trying for baby #2. Now I have never been the healthiest of woman but I always maintained my weight and also made sure to lightly exercise during the day. I hadn't changed my diet or exercise in any way at all. For me to gain that much weight in three weeks and barley be able to fit into my shorts blows my mind. To take the weight back off, I'm eating mostly greens and sticking to the "My Fitness Pal" app and walking A LOT. I guess I just want to know if any one else expirenced this after taking out the nuvaring?