Yesterday I went into the bathroom & flipped the light switch and, nothing happened.  Figured it was a bad switch & was going to save it for today.

This morning I got up & went to the bathroom and without even thinking about it I flipped the switch and the lights came on.  Then I remembered that they wouldn't come on the day before.  I stepped out of the bathroom and they flickered off.  

So I changed out the switch & still couldn't get the lights to come back on.  Changed out to yet another switch just to be sure and still, the lights wont come on.

What's my next step from here?  Should I try rewiring the fixtures?  Am I looking at a bigger problem here?

Are the fixtures recessed?

No

Ok.  I would start with checking the wire nuts at the switch box and at the fixture/s.

What type of fixture/s do you have?  Is it multiple or a single fixture?

The switch controls two fixtures.  The one over the sink is a dual fixture and the one at the center of the ceiling is a single.

ETA - thanks for jumping in this thread BTW.  Electrical isn't my strong point.  I bought the house 1.5 years ago have found that the previous owners did a very haphazard remodel.  Things break/wear out & when I have to dig into it it takes longer because I've got to redo everything.

If both lights are out I would check all connections in that room.  From where I sit it's hard to tell if the source of power is in one of the fixture boxes or if it's at the switch.  It could also be from the GFCI recep in the bath..  If any of the fixtures or the GFCI has a back stab or push-in connector that's often a source of intermittent power.

Did you turn the breaker back on?
Sure the bulb isn't lose or bad?

Do you have 120v coming into the switch box?

Look at the switch wiring connections and see if the wiring is 'push wired' or wrapped under the screw heads on the side of the switch.
Push wiring is just bad.

***Great Success Update***

Today after church I tore back into it all.

One of the connectors in my ceiling light had come loose.  Of course, it was the last one I checked/redid.  Once I got it back together I flipped the switch & had light in my bathroom again.

When the owners before us did the house remodel, they used stab connectors for everything.  As plugs and switches have gone bad I have replaced them with new plugs & wrapped the wires around the screws.  It does make for more reliable connections.

Thank you to everyone who popped in with a suggestion, especially billhw1.

Yeah, that's the way it works in my life too.  You'e welcome, glad you got it wrapped up.