Red spot?

My 3 month old EBF daughter had these red spots on her leg when we woke up this morning, but they weren’t raised or anything so I assumed they were from her pajamas rubbing her leg or something. Now the bigger ones are slightly raised like bug bites and they haven’t faded at all. They don’t seem to bother her, they’re nowhere else on her body, and neither I nor my SO have any. We do have a dog, but she’s regularly treated to prevent fleas and she hasn’t acted like she has any and we haven’t seen any on her so I don’t think that’s the issue. I’m keeping an eye on them and I’ll call the pediatrician if they get worse or don’t go away, but does anyone have any idea of what they could be?