1) R.A. & Dec are fixed coordinates. Except for errors like precession, they do not change for fixed objects such as stars.

2) You were not looking with a telescope. Vega is a daylight object in Jan. and is easily seen in the northern hemisphere in Jan., if you have accurate pointing with a high contrast telescope.

3) Day would become night in about eight minutes. Panic would ensue... Events beyond the 10 minutes would be catastrophic.