I am originally applying for MPH program. and got accepted by UCLA. And I requested to transfer to MS. (As an International Student, MPH may be troublesome.)
UCI haven't given me any responses yet. They said they were stil processing. But I have accepted UCLA's offer. No worry.
I think your experiences are more than qualified to attend this program. I don't know exactly your GPA and GRE, can't give an entire evaluation.
Cal State are not bad. MPH programs are pretty accessible! Be confident.
Prepare your GRE and SOP!