cramping and pumping

😀
I have a little one in the NICU so I'm pumping every 2-3 hours around the clock. I am barely getting a 1/2 ounce on each side when I pump. I am 1 week post emergency c-section and baby was born at 34 weeks. Also, when I pump I get cramping like period cramps pretty bad. Maybe two or three big cramps in the 20 minutes I pump. They are very uncomfortable. Is all of this normal?