Re: bricks in my mouth
Mrmarzipan, I know EXACTLY how you feel. The first time I had an impression taken I was 16 years old and I was so excited to be getting nice shiny teeth, and as soon as that gunk went in my mouth I gagged and gagged. I didn't think I'd be able to bear wearing the denture when it was ready. Sure enough, when he put it in, I gagged again. If I hadn't had such a lovely and wise dentist at the time, I probably would have pulled it straight out, but he said to me "just keep your mouth closed, breathe through your nose, don't talk for at least an hour, it will be fine." And guess what? He was right!
That was many years ago, and a few months ago I had to get a lower denture, so I had both upper and lower impressions done for a whole new set. I was sure I'd have no problems, being as I'd worn my upper denture for so long, but as soon as he put that gunk in, off I went again. So much for him telling me it was psychological, ha! If it was psychological, then my attitude (that it wont happen this time) would have prevented it.
When I got my new upper denture, I put it in and yep, you guessed it, I gagged on it. It felt HUGE. But I remembered what my dentist of so many years had told me, so I closed my mouth, breathed through my nose, and didn't talk for 2 hours. (The not talking was the most painful for me, lol). And now, I'm not even aware I have it.
So what I'm saying to you is, please DON'T give up. Impressions make a lot of us gag (they're a LOT bigger than the denture will be), and the first few hours of wearing the actual denture might (or might not) also feel uncomfortable, but you WILL get used to it much faster than you currently believe. All you have to do

is "close your mouth, breathe through your nose, and don't talk for a few hours!"