Overflowing AM, empty PM..HELP!!

I need some help and advice. Baby is almost 10 weeks old, EBF on demand. Every morning I wake up and my right breast and sometimes both are so full that my let down is forceful and baby has a hard time. I've tried expressing first but it's still fast! So usually I'll pump during his first nap between 8-9. I get usually 5-7 ounces if I pump it all. Then feedings after are good until the evening. 
Then by the mid evening my milk is so low that baby gets frustrated and won't BF! He will latch and suck but them come off getting all upset like it's empty. How can I get my supply to even out throughout the day? Should I not pump in the morning? He also only eats from one side at each feeding so I am concerned that my supply will decrease if I don't pump.