Hi I Am 24 I Never Mastrubate Few Days Back

Hi
I am 24 I never mastrubate

Few days back I made sex with my girl friend.

But when she gave me blow job
She feel some stone type something.

Now today's night I tried mastrubation for 1st time.

And me too saw some stones type something around my penis.

I have carefully removed them.
But is it Normal
Or i need to worry about it.