Hi group

This might be a non-issue but here goes:-

I'm a 41 year old male non-smoker from England and I weigh around 180
pounds. I've recently had a severe chest infection that's lasted for a
month. My GP prescribed a Ventolin Inhaler to keep my airways clear while my
chest recovers. I've never been asthmatic or had any other chest problems
and I'm not too sedentary.

When I use the inhaler I feel faint. I presumed that it was something to do
with the contents of the inhaler, perhaps the propellant, but I've just
noticed that if I fill my lungs and hold my breath for a couple of seconds I
feel very faint rapidly. I'm sure that this didn't used to happen. I could
always swim underwater, for example, for quite a while with no problems. Now
while holding my breath my pulse seems to disappear. It doesn't appear to
slow down or speed up just gets faint and disappears.

I did speak to my GP about a year ago because I was concerned when from one
week to the next I noticed that my pulse rate had dropped from around 70 bpm
to 48 bpm while resting. It's still 48bpm to this day although I haven't
really suffered any ill-effects from it. When I run my pulse speeds up as it
used to.

Does anyone think the feeling faint while holding breath thing sounds
abnormal or am I just being a bit of a hypochondriac? What about the 48 bpm
pulse thing? Possible cause for alarm?

Regards