FaceTime or Snapchat Video chat hack

Well this is not a jail broken phone and yet still someone albeit more than on embedded themselves into my phone. The video chat started out on snapchat i felt comfortable with her so I gave her my number. Then we proceeded to talk on FaceTime. Now here is the strange part almost the whole time she was checking her phone and also clicking away at a computer which she says was a Mac and also repeatedly muted the call to answer her cell phone and at one point someone’s contact appeared on my screen for like a split second anyway after that I put my phone on the charger and went to sleep and when I picked up my phone the first thing I saw was that my emergency contacts were open and there was a new phone number marked as Son and I don’t have kids when I checked when it was changed it was 8:48! I think right at the time of the video call also looking closer at it and checking my recent calls the FaceTime call and the new emergency contact where the same number. Of course I called it put it went to a google voicemail so probably a untraceable google number right? Ok so I have reset everything on my phone and was actually in the process of buying a new one anyway So now I ask has anyone who ha something HELPFUL to say I would appreciate it thanks