So you shoot your future self because he was monopolizing your other future self in the timeorgy.
This is a case of "I don't want to go blind, but can I keep masturbating until I need glasses?"
So what if there's like 15 of you fucking you and getting fucked by you and it's complete heaven for every one of you except for the guy shooting you, who you've already been, and the guy who gets shot, who you are not going to be until you get around to being serviced by, and serving every other you with their pants around their ankles at the time orgy.
You'll keep going back to the start of the time orgy as a different participant because it's further along in the future and you're still you, even though you keep thinking (Russian roulette with your dick is an Eddie Murphy joke) "I really shouldn't keep going, it's not safe, but it's fun as heck, and so long as I'm sure it's not yet my time to get my face blown off, it's more orgasms right now for me and me and me and me and... But certainly I'm sure I can paradox out, change my fate and save myself just before I did shoot myself because I'm not as dumb as the dick head I already shot who happened to be future me when I was past me. It's all good as long as I can count to 15.