I caved. Is it too late to get out?

The male in question and I got super high last weekend and I declared that I was in love with him, and allowed that to motivate everything I said/did while under the influence. Unfortunately, my feelings for him are not as strong as I let on. After a lengthy conversation in which I explained that I was not in a position to date him, he somehow convinced me to give a relationship a shot and see where we go. I agreed feeling that there was nothing to lose. A few hours later, I'm feeling absolutely disgusted when I look at his picture, dread seeing him, and can't imagine us in a relationship at all. Are these just jitters--perhaps related to me being scared of heartbreak--or a serious sign that I need to call this off? If the latter, when and how do I do this respectfully? Apologize for letting him on in the first place? Thanks for your mature responses!!