Hello,
Sometimes students tend to be very tense during their first pool diving sessions, they might contract abdominal pectoral intercostals muscles (and respiratory muscles) leading to lactic acid accumulation and that might hurt while breathing.
What about the tuning of the regulator? Did it breathe smoothly or a lot of inpiratory efforts?
About pneumothorax it has been reported to have happened in a pool, but never my colleagues diving physicians reported such event.
But they also told me that 1-meter of water was enough to generate a pneumothorax if a deep inspiration was performed before going up...
Symptoms and signs of pneumothorax are: Shortness of breath, cyanosis ( blue coloration of skin, nails, lips
),rapid and superficial breathing, pain in the chest ( should be present in inpiratory and expiratory phase, not only while deep inspiration.
There might also be a sub-coetaneous emphysema (crackling feeling under skin of the neck and/or chest)
Maybe you inhaleted some water?
If this sensation persists seek some medical help.
But it doesnt alarm me, as a few of my diving students reported me such symptoms without any severe issue.
fa.
Other doc's will come up soon!