Birth Control

I had been taking birth control for about two months and I gained at least 20 pounds. I am a runner so I run everyday. I stopped taking birth control because it took away my competitiveness and I felt like an anchor running. I’m wondering when I will lose the weight that I gained from the birth control. My hope is it’ll start coming off easier after it’s been about two months since that’s when I noticed I gained an excessive amount of weight..is this logical? Can someone help me or give me tips on how to lose it?