I'm suffocating, help!

You may not need to exhale as much air as you're using. Try the warm hand exercise (from Harmonica For Dummies):

1. Place the palm of your hand an inch from your mouth.
2. Exhale gently from your mouth so that you can feel the warmth from your breath, but not the wind blowing against your hand.
3. Now use the same amount of breath to play a chord or a single note. The note(s) should sound.

This is all the breath you need to sound a note. Try using this amount of breath to play, maybe slightly more if you need more volume.

If you still need to inhale while playing a series of exhaled notes, look for a logical place to stop and inhale:

• Every melody phrase has places where a note lasts long enough to shorten it slightly to take a breath (usually at the end of the phrase).
• Repeated rhythm parts may not have pauses, but you may be able to replace one of the notes with a quick, discreet breath.

Remember, to take a breath you don't need to take the harmonica out of your mouth. Instead, let the harp rest on your lower lip, and simply drop your jaw to breathe over the top of the harp, then raise your jaw again to resume playing.

Hope this helps.