when will my supply regulate

How do I know if it regulates? I feel like a cow. I pump every 4 hours during the day and lately my almost 10 week old has been sleeping 5 hour stretches so I've been going 6 hours at night. And I wake up engorged and pump to empty and produce like 12-15 ounces at night. During the day I pump like 10 ounces at each session. I've tried freezing my milk but doesn't seem to freeze well... I keep freezing my leftover just in case lol. I'm a FTM and just wondering when I can drop more pump sessions?