Needy boyfriend is making me angry

Yesterday I went back to my place after spending almost 1 week with my boyfriend. Today we were both of work, doing our own things at our own places. He’s called me 18 times on FaceTime in the last 9 hours. The first time was okay, but then he just kept on calling and I got so annoyed that I started yelling at my phone before picking up. Every time he’s called me we talk for a few minutes, he just asks what i’m doing every single time and that’s it. “I was just checking in”. We also talk on snapchat every few minutes. I don’t get why he’s suddenly being so desperate and needy but it’s slowly making me ignore him because he’s being annoying. I know that if I ask him why he’ll be upset or defensive.