Unfortunately, all Tinymights have this inner glass sleeve, it channels the air from the top holes down beneath the heater. Open yours and take a look. But they designed it so the glass is just wedged between two rings of metal, no silicone or shock absorbing gaskets, so I guess I'm not surprised this crucial piece of glass can't survive long-term.
I was very careful with my Tinymight, it had it's own case and everything... It was a great vape while it lasted, but I think the repeated insertion and removal of the glass stem stresses the inner glass sleeve. The bottom metal screen presses directly on the metal ring connected to the inner glass, that's why they say not to tighten the top o-ring too much. But with this defect it's like a ticking bomb just waiting to crack, so sadly I don't think I'll be able to justify a replacement. R.I.P. Tinymight, you were a great little vape, I'll be back when they come out with an improved version 2!