a couple pumping/storing questions

hellocarebear

First off, I had read that you want to pump until your breasts are completely empty. During one of my sessions today it took about 50min for that to happen.

My question is, is it okay to pump for that long? I'm currently pumping every 2-3 1/2 hours trying to stabilize my supply (i ep/don't bf) but I don't know if there's a such thing as over pumping?

 Also, a question about storing, is it ok to freeze milk that has been in the refrigerator for a day or two or does it have to be freshly expressed milk?  

  TIA