Swelling?

Hi✨

I’m currently 37 weeks pregnant. I am skinny, especially you can tell by looking at my legs. Today I looked in the mirror and saw that they are way bigger than like a day or two ago, they feel heavy and by the end of the day they kind of hurt as if I walked without stopping all day long. My knees actually look like they’re super fat and so are my thighs. I don’t know if it’s swelling, but I’m pretty sure my legs couldn’t just get super fat in a day or two. Anyone on here experienced this? I’m pretty sure I’m not making this up as my hubby did confirm that they look different.