Congratulations! As a fellow comic creator who posts on Reddit, I'm actually surprised this is the first time you've hit the front page - I feel like I've seen your stuff pretty frequently and you seem fairly well received most of the time. I've hit the front page a couple of times (Asian Superman being my most upvoted one) and it's always a nice bit of affirmation.
As for the negative comments, maybe I've been desensitized by my extensive internet experience, but I really don't feel like it's that different from most of the internet. From YouTube, to Twitter, to Facebook, it feels like anytime someone's given an opportunity to express that they dislike something, they'll do so. Honestly, sometimes I'd prefer seeing a number of negative comments as opposed to seeing a 62% upvote to downvote ratio with no one telling me why they hate an entry so much (though, these typically tend to be for my more politically inclined entries, so I can kinda fill in the blanks myself).
Also, an interesting thing I learned recently, Reddit apparently has followers now. Maybe you already knew about it, but I browse Reddit through its old format, which doesn't display followers on your profile, but it was news to me when I heard about it.