Your work doesn't look like it's getting worse, to me, so it may be some variant of that infamous gap from the Ira Glass quote:
or one of the "art lows" where your perception starts to grow faster than your skill, so your art "looks worse"
I don't think this could possibly hurt! If there's aspects of your art that you still don't feel are at the level you want to be, then actively looking into what could be improved in those aspects and working on them specifically ain't a bad idea!
And I do think it's a good idea to specifically practice outside of your comic. If all you're doing is comic work, for me at least, it's easy to feel like you don't really have a chance to dig in and grow -- because a lot of those "level up" moments happen not when you're making pages, but when you're sketching the 15th or 20th head on a page full of heads in profile trying to figure out how to make them look right.
I definitely did have a period of time in college where my art actually got noticeably WAY worse. I know I've shared this story before, but the short version is that I had a professor who suggested I use a different style of guidelines when I drew heads and faces, to give them more structure. It did make them more solid, but it also made them stiff and awkward. I showed my professor, and he insisted that I keep trying to get the hang of it. Since I'm stubborn, I decided I'd use it for all my art, because then if I got the hang of it and it was still horrible, I could say I'd really given it my all. There's a whole chunk of time where all my character faces feel stilted.
In the end, my professor was right, and my character art improved LOADS.... but it took an entire sketchbook's worth of frustrating drawings to get there.
TL;DR
I think it's not a bad sign if you feel like your art is in an awkward place or not getting better. Keep striving to improve the things you're not happy with, and keep practicing to get the hang of the things you're struggling with, but know that it may well just be that you're getting less satisfied because right now your brain is improving faster than your hands, and your hands just need time and practice to catch up.