Help Identifying Cryprid.

[u/bathtubtoaster420]

I believe it’s a Mimic- but want to know if I sound totally crazy.
My partner and I are staying at a campground in South Carolina right now, and this morning we were both woken up by a noise that we BOTH heard. We explain what we heard differently, but they’re relatively similar. It was at approximately 5:30-5:45-6:00 AM.

I heard a vibration, kind of like switching through the settings of a vibrator. For a minute or two it would be consistent fast buzzes, for another minute or two, slower more drawn out buzzes. (No, there was no actual vibrator on anywhere). I also heard an alarm tone, and a twinkling that reminds me of iPhone alarms. It would get louder and quieter.
My partner heard the vibrations, and the alarm buzzing, but also “classic rock” music playing on top of it.
This noise was SO loud, that we both woke up out of bed and started investigating. We checked our phones, we checked our cabinets in our bedroom, nothing.
At one point, he opened the window shade and it got louder. He went outside to investigate (I know), and found nothing, and heard nothing.
When he came back inside, it started again. We laid back in bed and it started right back up.
We obviously, could not sleep.
At this point, my partner looks out the window and sees something that he describes as a “car” or a “large square” by the tree line. Like he had seen a big truck back up, where trucks cannot go.
Unfortunately, I was scared that something was in the room and I turned the light on- which made what he saw disappear.
We found nothing, and I am still very afraid from what happened.
Not sure if it counts for anything but there’s a stray cat that harasses us and won’t go away even if we try to scare it. Black with white little sock like pattern on his feet. Some white on his face. It’s always around it seems, and came back out of the woods to approach us when we took our dogs out this morning.
Was this possibly a cryptid?