I restrung my Caparison TAT II from 9-46 to 9-42 and readjusted it to my best ability but now there's buzzing when I play the second fret on the high E and B string, how can I fix this? Also, how can I check if my action is low/high enough?

Since it's buzzing so low on the neck, it sounds to me like you need to add some relief to the neck.
This said.. since you ask about how to check if your action is low or high enough, it sounds like you should hand the guitar in to a guitar shop and have them sort it out for you.
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