oh gosh, if you managed to get her to take one yesterday, definitely keep it up!
dd1 was easy peasy and didn't care where her bm came from, me or a bottle. i would express quite a bit anyway, so always had plenty of milk. she did self-wean at 6 mos though - just preferred the bottle by that point as she could look around etc. v nosy.
ds1 refused a bottle point blank, and we went through every bottle, teat, sippy cup, cup and tea spoon known to man (as did everyone in my socila network and the hv, and the bf clinic. 
) in the end i had to go cold turkey with him at 10 mos because she wouldn't drink out of anything except me. so please do carry on with the occasional bottle!!! (he fed every 2 hours day and night. i was a sleep deprived maniac)
i used to express first thing in the morning with dd1 as my supply was better then, rather than when she was taking a bottle iyswim, but tbh do whatever works best for you. i've also been known to express in the car (when someone else was driving, obv...) or any other time when there wasn't much else going on - not sure what passers-by thought, and don't care really!
i had a friend who chose to give the baby a bottle feed for the final feed of the day, so that she would be used to dh doing it and would have a little more freedom to go out/ have an early night etc. so it was a routine that they all got into. i think she expressed in the morning as well. this was from about 6 weeks i think.
dd is still v little though, so i would make sure that you are still feeding or expressing every 4 hours. i wouldn't be worried about nipple confusion at this point - i'd be more worried about leaving too big a gap and her refusing a bottle again! (but that's from personal experience lol)