Cheers to that, @Love_and_light- sometimes there are aspects of spellwork that are out of our control (like when the Universe has its own plans, or certain deities known for being difficult to appease, etc) but our own mindspace is something we do have control over (even if it is a difficult skill to master!) 
I think it takes strong self-awareness, a meditative mindset, and a responsible caster to be able to take a step back from yourself and say “I’m just not in a good mental place for spellwork right now- I’ll come back to this later when I’ve calmed down”.
Which reminds me of an interesting discussion from a while back about casting while in a heightened emotional state- I stick to my response back then, with one exception: I imagine casting with heightened emotions could potentially be okay (or even encouraged!) when it comes to the lawless world of Chaos Magick 
I’ll stop rambling now, but these are all interesting points to consider! I’m also really enjoying reading everyone’s first learning experiences- there are some really great tips and advice here 
