Does this nurse totally not like me??

Today was my last day of training as a nursing assistant. I am in the float pool, but I trained at a med-surg floor for 2 weeks because that is one the training floors. During the first week of training, there was a nurse who was also the charge nurse. She said hello to me and asked me if I was training. I told her yes but I will be in the float pool. When I went to get something in the break room, she was eating lunch so I told her to enjoy her lunch and she said thank you and smiled. I had a few of her patients and told her the abnormals regarding pains, blood pressures, sugars, etc. A few days later, I made eye contact with her and she just looked the other way. I thought it was nothing. However, I went into the utility room to get linens and pads for patients. While I was going in, she was about to come out, but she saw me and turned around and got something from the linen cart. She just picked up a towel. I smiled and said hello. But she didn't even look at me and just walked out. It's a small room so I know she heard me. I started to think if I did something wrong. Did I tell her things about patients and she was bothered? or was she annoyed with me. Am I overreacting here??