Sleeping through the night

My one month old has colic (or something) that keeps her up and crying from 9ish to 1 am ish.  Once I finally get her down she has started sleeping through until 7 or so in the morning. I am not complaining about that part. I just wonder if it is ok for her tiny little self to go 7.5 hours between a feeding?? I want to encourage sleeping through the night especially because of how drained I am from the colic fits. Also I am breast feeding. When I wake up after sleeping for 7 hours my boobs are ready to explode. Waking up to pump is more trouble than waking up to feed the baby. Any advice on this from experienced moms?