Keep a paper bag with you and when you start to hyperventilate, use it.
I am going to put this in here for all...............information only.....I am not a professioanl.
Hyperventilation is "breathing fast," or overbreathing is commonly caused my anxiety.
Breathe into a paper bag. This has long been the primary treatment for hyperventilation. The theory is that rebreathing into a paper bag will allow you to replace the carbon dioxide "blown off" while hyperventilating.
Blowing into a paper bag is fine, if you've hyperventilated before, been evaluated by a doctor, and are sure there is nothing seriously wrong. Most people who hyperventilate meet that criteria, but a few may have more severe problems. Let Your Doctor Diagnose if this is new to you. Reference: Medical and Surgical Nursing; Willimas and Hopper
Your in my prayers, Aussie, and on my radar so I will be back later to check in on you.