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As long as you have a solid seal on the jar you are fine, but check it occasionally since the food could have contaminated the seal to cause it to weaken eventually. Perhaps put that jar at the front to be used before the others.

During processing the contents heat up and expand and the air in the "headspace' is pushed out. If the headspace was a little too small, a small amount of food would be pushed out also. That is what you experienced. When the jar cools everything shrinks back, creating the vacuum and solid seal of the lid.

You could increase the headspace to prevent this, but it is a double-edge sword. If the headspace is too large it leaves air in the jar that can discolor the food and cause other issues. The same goes for "bubbles" that weren't removed from around the contents of some foods.

I might also comment that it is important that the spring lids be tightened only "finger-tight". Too tight and that purging process may not occur, leaving air in the jar; it could burst the jar; or it could cause an explosive purge when the pressure builds up sufficiently. This will be evident when your jars are half empty and contents are in the canner water.