Is my girlfriend lying to me?

So today she is hanging out with her friend. Her friend influenced her to smoke week and get drunk and I didn't like that, this was like 8 months ago. My friend said she doesn't do that anymore.

So I was texting her and she said she was walking around with her friend to get icecream (icecream and stores is around where she lives). She stopped texting and when she replied she said she was going through her closet. I then asked what happened to the icecream and she said "remember I told you I was waiting?" She never said that.

She then stopped texting and when she responded she said her phone died. She said "it was like charging and then it stopped working" which sounds like crap. Now I'm thinking okay phones back on it should be around 5% since it died. I asked what she was doing and she said she was heading towards to get icecream. I then ask how does she have battery? She replied with she has 30% which doesn't make since to me..

Is she lying to me?