Bump on neck?

I have a bump on the left side of my neck. It hurts very badly. I just noticed it today and now it feels swollen. I looked at it in the mirror and its kind of big and looks like there is pus at the top but it wont pop. I was going to wait for it to go down but I searched the internet and some people say I shouldn t wait. Do i need to see a doctor?

2017-04-11T00:37:33.809Z