Sims 3 sim glowing blue and when around other sims, sims then run away screaming?

My sim owns the elixir shop and I keep going in there trying to buy stuff, but the cashier sees me and runs away screaming. My sim is glowing blue for some reason. I’m able to talk to other sims and they don’t run away, but I can’t buy stuff since the cashier keeps flipping out. What is wrong?