Nanny concern

Hi all - Mother of a 8 months old here. Recently hired a Filipino nanny (just 2 days back). She said she comes with 18 years of experience. She seems to be good with the baby (I am currently working from home, so I can see her genuine efforts to connect with the baby). I had asked for a reference of the previous employer and she gave it today. Nanny was playing with the kid in the living room. I called the number and somehow the person knew I had a daughter. And she gave random info on how the nanny helped her sister in law as well who is in Canada etc etc. so after I cut the call, I heard the nanny 's phone continuously ring. I wanted to give her phone and I saw the message from previous employer saying "hahahah". I just read this. But now I am so confused if I should confront her. Did she just ask one of her friends to pose as an employer? Or am I over thinking this and should just leave it? Let me know guys.