> Side note: How do I know if someone downvotes my comments? On Reddit it's easy as you can see the score, but here? Am I missing something?

Here, you can see the score on your comments when you are logged in (your comments have a red asterisk and the point score before your name, others comments don't have either feature.) Additionally, if the net moderation is negative (net score is 0 or less, since score starts at 1) for any comment (yours or not) the comment will be greyed (moreso the more negative the moderation is.)

The only way to know is by noticing the comment's score changing.