I agree with Joe. It's more probable that your tensioner loosened, a notorious problem unless you secure it to the frame, and got into your spokes.
To avoid this get your tensioner alignment perfect, even if it requires a little twist in the bracket to get the wheel aligned with the sprockets, then drill a 3/16" hole through the tensioner bracket and the chainstay. Install a #10, grade 8 screw through the hole and a lock nut with Loctite on the inside (wheel side). Be sure to position the tensioner so you'll have room to move the wheel up or down to adjust chain tension.
Some guys here do not use a tensioner at all and avoid the hassles. However that requires shortening the chain and leaves little room for adjustment when the chain starts to wear and stretch. That's something else to consider. The kit chain, usually #415, is not the best quality. Look for an industrial supplier near you, Grainger, Tractor Supply, etc, and pick up several feet of good quality #41 chain. It's slightly wider but unless you buy the real cheap stuff will run smoother and last longer without significant wear or stretch. Good luck.