Help required on Nexus 5 Charging ICON

Hello, my friends,

Greetings from a old timer. I am a Nexus 5 user and my OS is 5.1.1

I have a LG Adaptor and I have a LG Cable to charge my phone.

Last night when I was plugging in my phone (I was quite sleepy), I saw (or I think I saw) the following:

- A charging ICON (saying Speed or Fast or something like that) and a 15% number
- On touching that pop up it vanished

Has anyone ever seen that ? I am trying to reproduce that and I am failing.

I have a factory build LMY48B and the Baseband version is M8974A-2.0.50.2.26

Please, can someone shed some light or was I seeing things ?

I just connected my charger cable to charger and the other side to the Nexus 5. Properly, I might add.

Thanks and best wishes

Sudipta Sen