Hey well done, that's a massive achievement. Have you had a look at your local leisure centre to see what classes they run ? I wouldn't suggest diving in and doing anything like zumba or body pump, but try yoga or pilates, which is about core body strength, posture and breathing. They are more gentle exercises but also very good for improving muscle tone, I am not very flexy so cannot do some of the positions but enjoy it because there is no pressure and you do them at your own pace.