Just wondering if y’all have experienced this...

Our son got diagnosed with pink eye Saturday morning and Seemed pretty miserable but still played and napped normal. Slept like crap Saturday night...seemed fine Sunday & we were out and about all day and he napped in car and what not normally..slept well last night but then today he’s soooo tired. Woke up and 45 mins After waking he took a 3 hour nap. We got him up to eat and now he’s back sleeping again after like 30 minutes. He’s congested and has a cough but no other alarming symptoms like fever, diarrhea of vomiting or ear infection. Obviously kids sleep more when they aren’t feeling well it just seems strange that it’s delayed? He’s had this cold since Saturday and today it’s like he’s feel worse than ever. Pediatrician doesn’t seemed concerned Though. How much daytime sleep is too much when sick? No limit? Lol