If HD is not too much out of the way for you, you may as well pick one up ( I noticed that you posted that yesterday) since you’ll want to get a new bottle anyway.
Recently I started a new bottle of O2, not because I used too much O2, but because I must have left the regulator open. The interesting thing was that with the same amount of bubbling from the wand it took me twice or more as long to get my batch to 8 ppm (ideally I want 10-12 ppm in a lager). I first thought that the DO (dissolved oxygen) meter is broken and I tested it in vigorously shaken wort which did show ~8 ppm. The O2 is a different brand than I had before and just to test this I’m going to pick up a bottle of the brand I used previously to see if that really made the difference. I was utterly surprised since I didn’t plan on having to mess around with oxygenation and repeated DO readings.
Kai