Pumping help

Hi!! So my baby is almost 3wks and I have to start pumping so I have some supply back up for when I go to work in 3 weeks. I just started today and with my first pump, I got a total of 1oz, this is combining from both sides...is that good or bad? One side def produced more than the other. I also think the flanges may not be the correct size, at least for one of my breasts...

I’m so new to all of this since it’s my first baby, and I don’t want to stress about it! Thanks!