Micro Sized Black Jumping Bugs?

I live in an apartment on the ground level. The other day I noticed that water had started to seep through in the corner of a particular wall when it rains by the front door. It's usually not a lot, so I allow it to dry on it's own, but tonight I looked over there and noticed these tiny micro black dots. I leaned in for a closer look, and only some were crawling so slow that you had to stare really hard to be sure. I grabbed a paper towel thinking that I could just wipe them up, but they started jumping. So, I sprayed them so long with bug spray that it literally drowned them. I didn't think to take a photo at the time, but they looked a lot like a baby ant in shape. I squished a few, and this brownish green stuff came out. I'm hoping that they don't return, but if they do, I will capture a few for a photo.