Your realisations about not wanting to make people worry sound like important ones! I'm sure some of those are behaviours you can change now that you've noticed them.
Just thinking about having to be by the phone all the time, or else drama, makes me so anxious! It does seem you need some firmer boundaries with your mother..
It's such a good feeling when your expections of major drama are met with an anti-climax like that. And then you feel sort of silly for building the whole thing up because the anticipation has been so much worse than it had been if you'd just talked right away. Been there, with different issues..