How many games before you’re tired?

I just got the game a couple weeks ago after it became available to download on PS Plus. I’ve been trying to climb up the ranks and I have made a squad I like. I feel I can only play 3/4 games in one sitting before I have to take a break. Every game requires so much attention and focus. Could also be that I’m in my 30’s lol, I remember in my early 20’s I could spend half a day playing games. So how many games are you able to play before you have to take a break?