Welcome - BW isn't a rigid schedule, so please don't get too focused on feeding to the clock. Tracy advocated following baby's cues, but sometimes they're a bit more tricky to interpret. Could you possibly be thinking you're seeing a feeding cue after 1.5h where it's wind (often looks very similar) or tiredness?
As for pumping, most mums find it easiest to pump first thing in the morning after LO's first feed. Milk is more plentiful then, so it's usually easier to get something out. Also worth saying that some mums can pump loads and some virtually nothing and this has absolutely no reflection on their milk supply and how much the baby is able to extract themselves.
With bottle feeds (whether that's EBM or formula) LOs will often take more than they need because it is easier to get milk from a bottle than from the breast and also they often don't get the 'full' signal as soon as they would by BF. If you're getting to the end of a feed and she stops and doesn't want any more, there's little point in pushing the issue. Trust her and trust yourself. Sounds like you're doing great
