2007 Accord - temp issue with ac and engine

This all started when I smelled coolant in the cabin. Checked coolant rez, it
was empty. Thought I had a leak, added more to see if I could see where it was
leaking from. After filling coolant rez, it dropped by about half the first day. So
probably have a leak somewhere. With coolant in the rez, I'm still seeing rise
and fall of temp and now the ac blows cold then warm. I'm not sure if the
engine and ac are coincidence or cause/effect. When the ac blows cold it's still
really cold.
Oh yeah, the fan stays on after I turn off my car. That started when there
wasn't any coolant in the reservoir and has persisited since adding coolant.
My wife just had a baby. Neither like being hot and I really don't want to
overheat with them in the car.
Thanks for the help