Yeah, Sharkey tends to be a pain in the ass for Kaity and Ada. I think it has something to do with the database, though that could've been from before Sharkey.
I doubt anything you're doing is bringing the instance down. I'd bet it just gets slightly overwhelmed at times (maybe because of some antennas?)
idk if Firefox focus does this, but on vanilla Firefox mobile, you can tap the text to expand it :3