Filing 2018 Taxes Late

I filed an extension (on 4/15/2019)  to file my 2018 tax returns.  Then missed the 10/15/2018 deadline.  

 

I am almost done with my taxes.   I will not owe any money because I am running a loss from my rental property business.

 

What penalties or fines is the IRS going to hit me with?

 

Thanks!!!