I am glad you got proper attention this time round. You shouldn't have had to go back.
Please pay no attention to the naysayers. I think there are people who have nothing in their lives but to sit around and make nasty comments to strangers online. It says everything about them and nothing about you.
I did sunbeds a few times in my early-mid 20s. That was back when you lay (in pools of your own sweat, yuck!) on the bed with tubes under and above you. I'm nearly sure that I did 20 minute sessions back then. I loved it when the standy-uppy beds became popular because they were so much more pleasant to use, and the only reason I know that you can only do a few minutes in them is because I used them. I haven't used them in well over 30 years so I wouldn't know the current guidelines, and if you're not a user either, then how on earth would you know? That was the salon's job and I really think they should be reported.
I think you should leave the thread up because, although there's a load of bullshit in it, it's a warning about the dangers of sunbeds.
I will never use one again and I'm sure you won't either. My DDs have never even though of using them, and I'd go mad if they did! They know what their aunt has gone through for the best part of 20 years.
I hope your skin heals quickly, and that you're not in too much pain. And don't be putting yourself down either. You've come across as a lovely person throughout the thread, even when posters have been mean-spirited x