I'm also a first time mum, our little girl is almost 8 weeks and I'll be 24 in February. We're quite similar in a lot of things you said, but unlike you I had a lot of sickness (4 months at te begining and the last month) so it seems I might have gotten your share too!
I decided to use the junior joy terry flats (it takes a long time for things to dry where I live so flats seemed the best option), but I am now moving on to fitted as they (strangely enough) fit better, and are also a lot slimmer, easier to put on/take off and easier to store "on the go".
I also tried breastfeeding, though there were some complications with our daughter in the first week were we were forced to feed her express milk via a bottle, which then led to her being lazy and getting angry at the breast as the milk doesn't flow as fast, so she is currently on a mix of EBM (expressed breast milk) and formula, but it seems the more time goes on the less I can express.
We were also lucky like you to get a lot of second hand things from friends and family, our old neighbor having twins, her sister having one and my uncle having a little girl who have all just turned a year last autumn/winter. We have hardly had to pay out for anything and what we did mostly furniture from second hand stores!