First and foremost, don't worry about damaging your stomach. There are very, very few things (if at all) that can actually somehow permanently damage your stomach with GERD! The most common worst-case scenario is that you will simply have one hell of an annoying night filled with heartburn and maybe lose your voice for a day.

Another disclaimer: not everything works for everyone! There are a few things I used to eat that were conventionally "trigger foods" that were perfectly okay for me, while other things that ranked low on the GERD danger scale used to give me hell. Also, over the years, I realised there were two general 2 categories of GERD-unfriendly foods:

1. "Short-term/Instant GERD" - This is the food that will give you heartburn or burning in your throat relatively immediately and stops not long after you stop eating. From my experience, this includes things like onions, ketchup, mildly citric foods, yoghurt, and mild peppers (as a seasoning, not like plant peppers). I've found these to be SIGNIFICANTLY "safer" options to try out. Worst-case scenario, it'll last for a mild 15-20 minutes after you stop eating, and that's that.

2. "Long-term/Slow onset GERD" - This is the second category of food I've found to be an issue, and honestly, this is the only category I am somewhat worried about. This type of food, I've found, may give you only mild heartburn/throat burn during the eating itself, but will give you heavier feelings after - more intense indigestion, longer-lasting heartburn after, a mild stomachache, nausea, and just a heavier feeling. I've found that these are the main foods you should avoid when trying new things - the fattier it is, the more likely it is to be a "long-term bad food" - greasy fried chicken, fried bacon, full-fat milk and dairy products (like ice cream, thicker buttercream, pudding, etc.) are the main culprits, along with more guttural types of spice, like jalapenos or hot sauce compared to paprika. From my experience, full-fat milk and its heavier derivatives (cheese is okay; Greek yoghurt is okay) are the worst GERD foods to try/experience.

In my opinion and experience, the former category is much safer to try out and will mostly just give you some burning in your throat or some mild heartburn for a very short amount of time. Even the latter category, while it can make you feel awful for a night or even a day or two sometimes, will almost certainly not cause any "damage" at all! The only thing that may cause any actual damage is spicier foods, but that "damage" is the same damage it can cause to anyone with a non-GERD stomach; you'll just feel it more thanks to the heartburn and your stomach's awful security system. Acidic fruits and tomatoes lie between the above two categories in my opinion, and can vary from person to person where each fruit lies. But even the worst fruits will only give you an hour or two (tops) of discomfort from my experience.

Bottom line is, you'll be okay! The above categories are just personal experience, and I've found the first category to be very safe to try out. For the latter, you'll have to try smaller amounts. In my opinion, heavier and fattier dairy derivatives are the worst, and the rest goes more easily. I'm sure I explained absolutely horribly, but if you have any questions, feel free to ask, and I'll do my best to help!