With no temp and creamy, yellow-white discharge, she's probably fine but I'd keep an eye on her anyhow. If the discharge was more green, I'd be concerned.
Glad to hear she got her IgG and was over 800, she'll most likely be fine. Probably got some shavings or dust up her nose and needed to flush it out with a good thick snot.
Having the vet out to check her anyhow is never off base with these little foalies, they can go down so fast it's just crazy.