Tingling

So I was washing my baby's bottles and as I was standing up by the kitchen sink washing them I felt a tingle between the bottom of my spine and top of my buttcrack.. I went to check if there was a bug crawling on me nope, I then checked if maybe a piece of my hair fell in in my crack nope lol

I've been feel this "tingle" for about a month now .. idk what it could be but I feel it a lot when I'm standing up.

Anyone know what it could be , I tried searching online and got nothing..