Petechial in 1 year old

Hi there.

My son (age 13 months), has had a petechial rash for over three weeks now.when it first appeared he also had high fevers and I took him to Hospital where he had a CBC done and the only thing out of range was a slightly raised CRP. He was given broad-spectrum antibiotics as a precaution and we stayed overnight for observations but left the next morning with the assumption of a viral infection. Blood culture and swab pathology tests came back negative.

His current petechial rash is quite minimal compared to the one he had a few weeks ago, however new spots keep coming up. He is otherwise healthy and happy (besides from teething blues), no more fevers.

I am not feeling concerned about any urgent/acute health issues as he is acting pretty normal. But I am a little concerned about a possible underlying health issue, and firstly wondering if this could be a side effect of Nexium? Or is it likely still a virus running its course?

Thanks for any help in advance!