Injured my shoulder and elbow while doing pull-ups

I took a couple of days off.
I was pushing myself hard through every set, thinking I needed to give it my all,
but when I woke up the next day, I had pain every time I moved. Ugh.
I don't think I've ever had elbow pain like this in my life, but after looking it up on YouTube, they say it's golfer's elbow. Apparently, it's because of poor forearm posture.
As I get older, I can't train as intensely as I used to. Don't get injured and remember to take it easy.