Knee pain

My right knee has been uncomfortable for some time. Sitting cross-legged is uncomfortable, and I flinch when I stand up after sitting down because of my knee. There is also a slight warmth. I wonder if it's because I've gained about 3 kilograms recently? I tend to drive a lot... Could that be the reason? My husband keeps telling me to go to the hospital, but honestly, I don't want to go. I have been watching many videos about knee pain on YouTube and TikTok. What should I do...ㅠㅠ