As with any type of art, the most important thing is uploading regularly. As for gaining followers, my experience is mostly with Reddit and Twitter, so I only really have advice for that.
I find reddit is a great place to get people to actually see your art, but getting reddit followers is next to useless. That's why I like to post my art on reddit and link my twitter in the comments. Early on 98% of my twitter followers were gained this way. I find this method makes it way easier to start getting views, because it's extremely hard to get traffic on Twitter without likes and retweets from people who follow you.
If you don't want to post porn, meme drawings and humerous comics are a sure-fire way to get your art to the top of a subreddit with relatively little effort. The great thing about reddit is that once it gets to the top of a subreddit, it stays there for around a day, and everyone who clicks the post will see your social media links.
Fan art is more powerful than original art, but less powerful than porn, so it's a good option for building an audience without selling your soul. Just be careful to keep posting a balance of original art and fan art if you want people who followed you for your fan art to stick around
From what I can tell, having accounts on lots of different sites is really useful. Some artists use postybirb to make uploading art to all of their accounts at once easier.
Lastly I checked your account, and your art looks good! You shouldn't have too much trouble getting a following. Hopefully some of this info can be helpful, I apologize if I was a little long-winded in my explanation. I found the experience of building an online presence intimidating as well, so I understand the struggle of getting started :)
P.S. I've found most of my success on my alt account, so the fact that this one doesn't have many followers doesn't mean these tips don't work!
Hmm, I would try uploading with Postybirb for now then https://www.postybirb.com/
It is a multi-site uploader, but it may help with making sure your posts go up on DA if you are struggling with DA uploads.
I don't know the issue to solve it from DA's end. The only time I have an issue posting on any websites is if my file is too large or if there is a connection issue.