Did I do the right thing?

My cousin confessed to me.
We have been friends since we were born. Our parents are siblings.... but he confessed to me. I never thought that he would feel this way. I kinda feel betrayed because I thought we will be best friends forever. I thought I was in a drama. Because thr c-drama I saw I had the same thing happened to trh female lead?
I have turned down other people without thinking much about it as I was not close with them. But I could not reject him I think because I did not wanted to hurt him.
Now we are a thing I don't feel anything. I'm confused.
I don't know why but somehow I feel guilty. Even though it is a long distance relationship by just chatting on the phone.
Did I do the right thing?
Can I get some advice please? I've no one to talk to as I don't want to make the situation awkward with my family.

Hi there
If he is your cousin, it is weird to be in a relationship with him. I do not believe it is normal. Plus it makes feel uneasy.
You should with him about how you feel and also that it is not normal for cousins to date.

Yeah, exactly! I feel really uneasy. I'm about to lose my mind since that day.
How do I end it? I don't have the courage. Plus, we are only texting since we don't want anyone to eavesdropping us.

Send him a message and tell him that it is not normal to date a cousin.
And tell him that if he insists, you will to tell the parents about that.