Bump under infusion site

Hi everyone- I just changed my site today a few hours ago and I just noticed a hard, pea size bump underneath where the old infusion site was. I didn’t have any issues with insulin delivery with the site. I do you my stomach a lot because I get the best absorption there, but I’m always careful with rotating. I’m using the medtronic mio infusion sets, and this is the first time i have encountered this. Has anyone else experienced this ? Should I be worried and call the doctor or is this something that will go away in a few days. I’ve been pumping for years and don’t remember having this issue before. Any advice would be helpful. Thank you!