I know it’s gross but I need some help. Can anyone identify what insect has bitten me?

The bites first appeared on Monday of last week and since then they have only gotten bigger. I don’t think they are mosquito bites because I’ve had a lot of mosquito bites this summer and all of them have healed pretty quickly without leaving too many scars.

These bites are incredibly itchy and really swollen. They appeared after sitting outside for a few hours in the evening but I was sat on a chair and there weren’t many insects out yet.. If that helps figure out where they came from? I also have 2 on my back which look similar to these and appeared around the same time.

Any thoughts?