You answered your question without even realizing it. It is always ok to care about your loved one, and it is always ok to reach back out to let them know you're ok, no matter the medium, no matter the circumstance. It is not irrational, it is human.

A college classmate on 9/11 died in the Windows of the World restaurant. Her death may be a statistic to you, but it is not to me.

I remember trying to call friends in NYC that day, all the exchanges were overloaded. I'm grateful that we now have ways to connect without worrying about possibly preventing emergency calls from going through.