How to tell if it’s infected?

Hi ladies, 2 days ago I had a tattoo extended, and the pain now is worse than the actual appointment. My foot is so swollen I feel like my skin is going to split open every time I take a step. I just took a cool shower and the water touching it made me scream. The first time round wasn’t like this. It didn’t hurt nearly as much. Could it be infected?

It’s not really red. Just very swollen and sore. It wept a bit but I think it has stopped now

Thanks for reading 😊