How much trouble can I get in for selling marijuana to a friend and them getting arrested for it?

I don't deal drugs and last night me and my friend bought a quarter of weed for $25. One of my other friends wanted to buy some and we texted about it and I sold him some. Later that night the cops took his phone(not sure if they went through it or not) and he was taken into jail for a few hours untill his parents picked him up. He told the cops he bought it off some random guy at 7/11. I'm just wondering what the cops can do about this and if I am going to get in trouble over this.