You've probably had urges where you really, really want to either make contact w/ your W or feel there is something you must really get off your chest to her, etc. Something makes this impossible, and by the time you can again, it seems less urgent or even isn't a big deal any longer. No real mystery.
Instead of trying to figure out what was going on w/ her seeming to want to talk, and then not the next day, just let it slide as one of those things that doesn't seem such a big deal with a night's sleep or time.
Oh, and errands "and things" can be really mysterious if you say the "and things" with the right intonation. Can be especially good if you can raise and lower your eyebrows. Seriously, you weren't available when she called and texted repeatedly. That's plenty of mystery, and is the kind of thing that has a deeper impact than words. So just let it stew for a while & see what comes of it. I admire the restraint you showed. I still have to work hard to catch myself not just instinctively jumping to pick up or texting back. Has always been my nature and habits are hard to break.
Me: 50 W:43 S6, S3 M: 12 yrs. T: 17 M is bad & Not happy Bomb Mar '14 S 5 Feb '15 D Bomb 13 Apr '15 (but "no hurry") DB Coach May '15 Wants proceed on D Aug '15 Starting 1-on-1 negotiations Sept '15