do you want the esoteric or scientific answer here?
there's multple ways of looking at this.
you're essentially opening a portal into the unknown, what's beyond those gates is almost always (in my experience at least) a total crap shoot, you just never know quite what you might experience or encounter. this is why I always suggest practicing unconditional acceptance and surrender especially in the face of something unfamiliar and uncomfortable. you can fight what ever it is that's making you uncomfortable but at the end of the day it has to be done in an appropriate manner which usually involves something along the lines of accepting the stimulus and expressing something along the lines of "while I accept your presence, I'd really appreciate if you'd give me some space and leave me alone for now"
the scientific answer?
hallucinogens / psychedelics like DMT, other tryptamines, indoles, and so on are essentially a biochemical cheat code. a "hack" you're introducing something to your brain that allows it to operate beyond it's usual operational parameters. when this happens it's only normal to have less than "normal" (what ever your normal might be) experiences. this is why these substances are so powerful in treating a number of psychological disorders and ailments such as depression and anxiety. you're essentially taking your brain which is use to things being a certain way and saying "now what if we took everything you're doing beyond the sympathetic level (i.e. breathing, heart beating, digestion etc) and we shake it the hell up.
so the esoteric? you've encountered a being or beings that speak a different language. nothing to worry about in my opinion so long as you don't take their pestering bullying to heart or seriously beyond someone making a small out of pocket comment to you. in all reality this is most likely your subconcious poking at your concious mind using auditory stimulus you've picked up through out your life and mix mashing it into its own personal language.
the scientific answer ? YOU'RE ON DRUGS


there's so much to DMT that we might never fully understand and you are one person in easily 2 percent or less of total humans in all of history that gets the priviledge of getting to explore beyond the unknown. for all intensive purposes you are in some ways a pioneering explorer. so, do human kind a serious favor and write your trip reports in as much detail as possible. the good, the bad, the ugly, all of it. sure it's all anecdotal but you never know when some other poor soul might be saying "why am I hearing strange alien voices when I'm in hyperspace"
Either way, be kind to yourself, use harm reduction and safe use practices at all times. and most importantly remember to have fun and just go with the flow.
Best of luck friend,

Neither Here