You don't need to know whether BB is full or not. He will tell you when he does not hv enough. Just direct BF him as he wants, that is. May be you will need to BF him once every 1-2 hours for the first few weeks. If he has 6-8 wewt diapers a day, he has drunk enough milk. The drinking pattern may make you tired in the first few weeks. But when BB becomes bigger (i.e. after one month), the feeding time will reduce.
Of course, you can choose to pump out to let sbd to do the job for you to relieve you sometimes, but not too much. If not, BB will refuse to drink from your Breasts anymore............You know direct feeding is very sweet. I miss it now (I turned to full time pumping from month 6 to now (month 13) because I go to work and the schedule cannot be matched with BB's feeding time. At month 5, he refused to drink from me directly.:-(
I heard that Chicco is the WORST pump of all. Try use medela mini electric, that is cheap and effective but quite noisy.