I've been talking to this guy I met on Snapchat.

I've been talking to this guy I met on Snapchat. He had accidentally added me instead of a friend of his. We started talking and it was automatically very sexual. He asked if I wanted a dick pic and I said no. We had only just met and I'm just not that into it. We kept talking and it seemed like that was it. When I woke up today we started talking like usual and he asked for picture I told him I just woke up. Not ready for pictures. A little while later he sent me a snap and just figuring it was a response to me saying that I will send him a selfie later. He wasn't asking for a nude just a picture. When I opened it up it was a picture of his dick with the caption saying he will send more when I send one. I just didn't respond. When he asked why o told him that I just said that I don't like dick pics. Should I have just rolled with it or am I justified with being a little upset?