What happens when a sales ociate forgot to scan a merchandise but still takes off the security tag?

Okay, last week I went shopping at Rue 21, and there was this sales ociate that forgot to scan a merchandise like a pair of jeans I had bought. The total was very small as I looked at the receipt, everything else i bought were scanned. My guess was that she forgot to scan the jeans, but ended up taking off the security sensor. I did not notice it was'nt on my receipt until 2 weeks later, so what will happen?