24 year old female, concerned about a shortened menstrual cycle, can anxiety provoke an early period? from 28 too 26 days ??

Sure: Stress and anxiety can affect length of cycle. So can other things, so if you are not pregnant and have no serious symptoms: fever, pain worse than normal, etc., see what happens next month. If cycle continues to be abnormal and get checked. First we check for a physical cause before saying certainly that anxiety is the problem.

Yes, not significant: Anxiety is known to cause changes in your period,, A two day change is probably not signficant.