It sounds like you're not rolling your body when you swim front crawl, which means your propulsion is not coming from your core, you're not aerodynamic, and you're using excessive effort to lift your mouth to breathe. Also, navigation in open water would be far more challenging if swimming on your back.
Take a look at Katie Ledecky swimming the 800 at the Rio Olympics, particularly the underwater shots showing how she initiates her stroke by rotating her hips.
May one assume that you breathe like a swimmer when you swim, and not like a runner? When I first took lessons as a newbie triathlete, the coaches pegged me as a runner, because I wanted to breathe in/out with a 50/50 duty cycle. [Wrong!] It was a conscious piece of retraining to learn to gulp air in quickly in a brief portion of the stroke cycle, then exhale the air steadily and calmly. If you are thinking "OMG I'm going to drown here," you're probably *not* breathing like a swimmer.