Thank you all for your replies. You've made me feel so much better.
I the suggestion of testing the frozen milk is an excellent one that I never would have known about! Thank you! I will do that tonight. I would hate to have all this frozen milk that wouldn't be used.
As for the deep freeze, I mentioned it to my husband and he dismissed it immediately. I'm going to try again, though. I think it would be a good idea even for the future.
I was able to get a fridge delivered to my room while at the hotel. I kept it refrigerated and froze it when I got to my sister's house (then transported the frozen milk in a cooler to come home). I drove, so it was easy to pack. I'm so glad I asked about a fridge.
I am continuing to see a slow increase in my daily production. Yesterday I got 5.25 oz! I know I'm still a long way from having enough, but I'm holding onto the hope that my babies will be much better at getting milk out of me than the pump is (BTW- the pump I use is the Medela Symphony, rented from a lactation consultant). And considering I thought I'd never get to breastfeed, since I don't get to be pregnant at all, I'm very pleased that I'm at least getting something. I feel like I will have contributed to my babies' health, even if I couldn't take care of them in the womb.