Urgent care or wait?

I found a lump on my 13m olds pelvic/hip area. I called his pediatrician, the soonest appt they have is Wednesday. I can’t stop worrying about this so I’ve been thinking about taking him to urgent care. My son seems completely fine besides the fact that he’s been clingy for the last couple weeks so I’m not sure if it’s urgent enough.

Should I take him to urgent care?