First time poster, so excuse me if my formatting is wrong.
Also excuse my english .

So I guess that I will have to give some backstory for you to understand this story.

I am currently in highschool, and my friend who we will call F, is in my class. As we both have one lecture that is a bit away from school, both on monday and tuesday morning, I will usually pick F up, and them leave him after the lecture. He lives about a ten minute walk from the building we have our lecture in. He usually texts me in the morning to ask if I will give him a ride.

This has not been a problem for me, as it is not much of a detour for me to pick F up on the way. I do not expect anything for doing this, except maybe a little appreciation. 

This was the case until last week.

Last week when we had just had our last lesson, me and F were casually. For some reason we got on the track of talking about me giving him rides on mondays and tuesdays, and the rest of the conversation unfolded like this:

Me: Imagine if I won't give you a ride next week (in a joking manner).

F: You wouldn't dare to do that.

Me: Okay, you probably shouldn't have said that.

F: Don't take that as I dare.

Me: I guess we'll see.

After that we parted ways, until tuesday morning (cancelled lecture on monday).

I didn't think this was too big of a deal, but I thought that it was a bit shitty of him to think that I somehow owe him a ride. I felt like he thought he could control me, so I decided that he wouldn't get a ride next week.

Tuesday morning comes, and so does the usual message asking if I could give him a ride. Here is how the coversation went:

F: Hey could you give me a ride today?

Me: Do you remeber last week?

F: Yes, that was nice of you (refering to that I went by his house to pick him up, and called him to wake him up when I arrived, because he overslept).

Me: No not that, remeber when you said I wouldn't dare to pick you up.

F: Yes.

Me: Well I am not going to.

F: Yes you are (in a half-joking manner).

Me: No I am not.

The conversation went on, and I thought that I made it very clear that I wasn't going to pick him up. He stops answering, so I guessed that he had accepted it.

I arrive to the lecture in time, wait for a bit until everybody has arrived so we can start the lesson. Suddenly I overhear the teacher read out a message saying "I am going to be late, I don't know where "me" is". This was from F, who obviously didn't understand that I was serious. Everybody around us who had heard what the teacher said were looking really confused, so I explained what you just read to them.

Everybody seemed to agree that I was right in doing what I did, and all of them seemed to find it kind of funny. F did not agree though.

We have allready started the lesson, when F comes in. F seems very mad, and said that he had to ask his dad to give him a ride, which made him and his dad late.

We talked later in the day about it, and he still seems to think that I am in the wrong. He doesn't seem to understand why I did it even though I explained my motives. 

I am confused now and need someone elses opinion on the matter, is he right? AITA?

TL;DR: My friend expected me to give him a ride, and when I didnt do it, he got mad. AITA?

