My 2 Year Old Keeps Waking Up With Rash On

My 2 year old keeps waking up with rash on her hands and face for the last month or so. I took her to urgent care the first time it happened and they said it was allergic reaction to a bug bite. She was good for a bout 2 weeks then woke up with another rash on her forhead and chin. They seem to go away after 3-4 days but it leaves her with a small tiny little pimply or bite for a few days. Not sure what it could be. I was thinking it could be bed bugs but I see no signs and I have not bites.Or dust mite reaction. I do have a lot of dust in my apartment. I washed all clothing, bedding, vacuumed and added mattress and pillow covers for mites and bed bugs. Things were good for a few days but broke out again. She does suffer from sinus allergies. Thank you