I am 18 weeks...I was actively working out before I got pregnant but the first 12 weeks I had some…

I am 18 weeks...I was actively working out before I got pregnant but the first 12 weeks I had some medical issues and was not allowed to work out! So when I turned 12 weeks I was given permission to work out again but I was so sick I couldn't! Now I am feeling great but don't even know where to begin but I really want to start exercising again! Any suggestion?