Bad taste in my mouth—anyone else?

First off, greetings to all the experts and specialists here!
So, here’s my question.
Lately, I’ve been waking up with this really unpleasant taste in my mouth. It's hard to describe—just a strange, off-putting flavor.
My teeth are perfectly fine—at least, that’s what my dentist tells me.🙂
I make sure to brush before bed and again in the morning, but still... that weird taste persists.😢

The big question is: could this be related to the lip piercing I have on the side?
I’ve had the piercing for two years now, but this taste issue is a relatively recent development.
It might sound a bit silly, but I wasn't sure—so I figured I'd turn to you all.

Thanks!

My old college roommate used to deal with this really sour morning breath, and from what I gathered through our late-night chats, it was almost always tied to some underlying digestive issues. In my experience, it usually comes down to needing a much cleaner diet or just staying significantly more hydrated throughout the day, but if things don't start looking up, you should definitely go see a doctor to get it checked out properly.

Yeah, I’m leaning towards some kind of stomach issue—maybe acid reflux? Honestly, it could be anything involving digestion at this point.
I doubt it's got anything to do with the piercing.

Yeah, I’ve definitely noticed that ever since I started college...
I'm eating way more often than I used to—and honestly, I've been stuck at a steady 155 pounds since I was fifteen, but I just put on about 11 pounds in the last two months... my diet has been pretty terrible lately.
What should my diet actually look like?

Oh, only when I don't have to take out my piercing.😁

Look, I’m definitely no nutritionist or anything, but I feel like most of us already know the basic blueprint for eating healthy: load up on plenty of fruits and veggies, toss in some probiotic yogurt or kefir, grab some nuts, and generally stick to seasonal produce and hearty stews. Cut out the processed sugar, skip those "diet" sodas and light snacks, and just make sure you're staying hydrated... honestly, don't stress yourself out too much over it—you can actually see a difference just by doing that.

Since this is your first time trying a sauce like this, if you don't feel any improvement, do yourself a favor and go get some actual tests done—check your bloodwork, maybe a urine test, whatever it takes. Don't be lazy about your health.

To be honest, I’ve never really had to watch what I eat before—so I'm a bit out of my depth here...