I used to get this rarely
usually after having too much sugar, which is a mild depressant
but yeah just, basically, don't let your feelings control you and don't question your self-worth, eventually our planet is going to be engulfed in flames, all of the work we've done will have been pointless, nothing lasts forever, yadda yadda, we might as well just make the best of it while we can
do what makes you and the people you care about the happiest, as it's all you can do in the end