Thank you for your question. Although starting 10 days early is not considered normal, there may be nothing to worry about. Sometimes our periods tend to shift and as a 34 year old myself, this has happened many times to me. I would wait for your next couple cycles to see if the abnormality continues, then contact your physician. If this is the first time this has happened, it can certainly be due to the stress that your experiencing. Stress can cause many things to happen to our bodies.
I hope this helps. Please keep us posted.