Knees are aching

Hi everyone, I've started noticing that my knees ache during and for a couple days after workouts. I've been doing HIIT and strength training. I'm super careful with form and I put my weight in my heels for squats etc, and make sure my knees dont go over my toes, etc. I also warm up before. I also wear Nike shoes specifically for these types of workouts and when I'm kneeling I'm on a thick foam mat.

I was told when I was younger that my knee caps are not aligned, and I went to physio for a bit. That was years ago and I haven't had an issue until now. Is that what it could be? Just wondering if anyone else has experienced the same.

Thx!!

Edited