First stage malfunction

Got my first stage serviced in january for the first time. First stage and regulator about 9 months old at the time of servicing. dove them about eight or ten times since the service with no issues. This incident happened on our third day of diving.

we had just passed the breakdown room when I started hearing bubbles that were noticeably louder than outflow across the ceiling. I couldn't feel anything coming off my valves or manifold, so i signaled my buddy and asked if he could hear them and shined my light behind my head at my tank valves. Buddy signaled that all was well and we continued down the line. i kept a close eye on my pressure gauge, and nothing unusual was happening. We went on for about 200 more feet and I called the dive. That little voice just kept saying, 'girl, it's time to go'. heading back, i was trying to clear my ears right before entering the solution tube when my buddy came up and grabbed me, pointing at my backup regulator. Im wondering why he wants it, but I pull it off my head and give it to him. He hands it back to me, yelling unintelligible gurglings through his mouth piece and starts pulling on my primary. So, I give him that one and put the backup in my mouth. I look at my gauge, plenty of air. He is messing around behind my head, and at this point I'm guessing that he is turning off my tank so I push my inflator, and it doesnt work. Okay, so the bubbles were not some evil leprechan in my head. Finally he comes back around and signals bubbles to me, so I show him my pressure gauge and tell him all is well, I know I have enough air for the exit. We exit without incident.

On the whole I lost about 50psi. Nothing significant given the type of dive we were doing, but it was a clear reminder of what can happen when things don't go as expected.

1st, I should have immediately turned off/on all of my vaulves to determine where the noise was coming from, signaled my buddy, and exited immediately.

2cd, but not necessarily ideally, If I couldn't determine the problem I should have signaled my buddy and written a complete description of what I thought might be going on, on my slate so he would have known what he was looking for specifically.

3rd, I should have turned the dive immediately after notifying my buddy that I was fairly certain something was leaking somewhere, period.

On the surface buddy told me that he thought I was asking him if things sounded funny, I was having trouble clearing my ears and he thought maybe I was wondering if I was hearing things, he said that when I lit my valves, he did not see any bubbles so he was wondering if I'd gone completely off my rocker because by then I had totally confused him.

I asked him when he saw that my first stage was leaking, why he didn't just come up and hand me his primary or give me an out of air signal, the most efficient way to get me to switch regulators, then tell me that he saw the bubbles, turn off my tank, etc. He said he didn't think of that until afterwards.

Bottomline is neither one of us did the right thing. But it was a good learning experience that thankfully was no more harmful than making us both feel stupid.