The way I see the "selfish" thing is very similar to a first responder views an emergency situation.

The number one thing for a first responder is to make sure it is safe for them to enter the scene, or the second responder will have 2 victims.

In the same way you are told on a plane to put on your mask first before helping another.

You are not a bad person because you care for your well being before caring for another.

It is rational self interest. This is the selfishness that Ayn Rand speaks of.

I am a first responder where I work (first aid - CPR) so i identify with your example. Thanks.

There are a lot of stellar Objectivists here, so if you have questions about any of the concepts please don't hesitate to ask.