What is it when several things happen at the same time?

Synchronicity is the Word that may be used to describe a situation where "several things" are happening at the same time. For example, while you are on the telephone, two other important phone calls also come in, UPS is ringing your door bell to deliver a package, and three electronic messages are coming in at that moment which require immediate attention. This confluence of events happens quite often. What makes synchronicity notable is that it often provokes anxiety, stress, or unhappiness. When good things happen at the same time, we hardly need or want to to know what Word to use.