Someone in the gym told me, "I have LSD, shrooms and DMT, just tell me if you want it." I want to try these but a bit apprehensive.
You should be apprehensive. None of those substances are for the feint hearted and in the case of LSD / shrooms, on a non microdose you're on the ride for quite a few hours so there's no getting out if you don't completely take care of your mentality / setting / people around etc. You will perceive your life differently on those two and you may not like what you perceive if you have any unresolved issues. I would strongly suggest extreme caution. I wouldn't say "don't do it", I'd say, don't do it unless you're completely in control of every aspect of it and have people who understand how to deal with someone who is not having a good moment. In the right moment, it is amazing.
To give you an example: I was once on a mushroom trip with a group and a person (also on mushrooms) initiated an argument with me, ie, they actually criticised me. Things took a very very strong turn for the worse and you don't really have any emotional defense for a moment like that.
DMT is quite something else. Most people I know who have been further than I have.. they don't regret not going back and that's always been a very strong guide for my own considerations. I took a low dose and came out of it to people saying "check he is breathing" ;-D I was fine, just had eyes closed and elsewhere. It really acts as fast as what I imagine an IV drug does. Also, it doesn't last 5 minutes, that's bullshit. It lasts 5 minutes and then you feel mildly stoned for the rest of the night. People exaggerate DMT as if it is the businessman's lunch but I can assure you, that afternoon is not going to be quite like the day before.