Back at the Gym

I signed up for some classes at the gym. I'm in something called Xfit and another called cardio blast. I do xfit Monday Wednesday and Friday and cardio blast Tuesdays and Thursdays. This is my first week doing it and I'm good and sore. I'm doing good with the weight training and core strengthening but the cardio is killing me. I just can't breathe and my chest gets all full of phlegm and I cough like crazy. I don't know if I'm pushing myself too hard because it's been two years since I've worked out. Nobody else seems to have any problems and I'm the only one who's breathing like Chris Farley in Tommy Boy. I hope things get better because I really want to fit back into non maternity clothes again someday.