While there are a number of possible mechanical problems mentioned before here, the main problem with wind instruments is 'breath control'.

Nerves don't help. And unless you can relax so that you can breathe correctly 'from the diaphragm' you won't stand much chance of regaining it in a hurry once you lose it.

And indeed, as is also the case with 'recorders' (especially 'cheap' ones), overblowing is the death of pitch & tone control.