Insect bite? Poison ivy?? 🧐 help!

What kind of bug bite does this look like? Or is it something else? It’s on my lower back on the right side exactly where my pants line is.

Quick backstory my fiancé was mowing the grass the other day and I was sitting on the porch with my son. When we came inside I was laying on the couch with a blanket when my leg gets itchy so I scratched it then I felt little welts like a mosquito bite but I had been inside for quite some time and didn’t see a bug flying around either. I looked at my leg and there was like 6-7 bumps all on my lower thigh and calf. Well the next day my back started to itch and well this is the result. It felt like mosquito bites too at first but my fiancé said it looks like a rash. Anybody know what it could be? Thanks.