Call for concern?

So my husband just noticed our sons leg today and said it looked a little swollen on the side as you can see. Has anyone had this happen to their toddler? It’s Friday night so his dr office is closed on the weekend and our hospital kinda sucks! He is 2 years old, he’s healthy and drives me crazy lol, he’s still running and playing with all his toys and a happy child. He looks fine so I wasn’t concerned till my husband keeps pointing it out and now it’s in my head stressing me and worrying me.