I don’t know what to do!!

This guy and I used to be my good friend in middle school. When I moved on to high school we kinda fell off because I was a grade older... Anyways, flash forward, now I’m 21 and he’s 19. He DMed me and we started catching up. He asked me to get coffee with him, so I did. That was late August/early September. We both don’t really have friends so when he asks me to hangout with him, I usually say sure. But when I do, I end up SO annoyed. He always talks about himself. If I try to say something about me, he always finds a way back to himself. He doesn’t shut up. EVER. Now I’ve been trying to pull away from him; telling him I don’t want to hangout or making up excuses on why I can’t. But he knows where I live and where I work. He shows up without asking first. He’s asked me to be his girlfriend twice and I’ve told him both times that I don’t want a relationship and that I only think of him as a friend. Then several weeks later he tells me that he’s falling in love with me. He has bought me $100 worth of giftcards, teddy bears, candy/chocolates. I don’t flirt with him at all. I text him one word responses every couple of hours. I give him verbal and nonverbal cues to show that I’m not interested, but he doesn’t catch on. I DON’T KNOW WHAT TO DO. someone help :(