Depends on your approach. If I trust my company and my position, no I don't fear. If I am long at all time highs(Like a rocket shape graph) on a manual photo camera making company, shares floating at 2 million and the paper ran from 25$ to 250$ in 3 days and I opened a position at 251$ at market close on wednesday evening, the next day is holiday and markets are closed until monday. I would probably grey out my hair that weekend and sit like a puppy on the corner while people celebrating new year or whatever.