Should I be upset?

I finally got my first job today. I'm 17 and I've been looking since I was 15. I've desperately needed this job because I need to be able to support myself. I told a few people I got a job, and the worst reaction I got was from my boyfriend. All he said was, "That's cool." When I asked why he wasn't reacting the way I thought, he said it isn't a big deal to anyone, it's just a job, and he's had a job for awhile now. I got a better reaction from my guy friend who isn't that involved in my life. My boyfriend has watched me struggle and be depressed all summer because I couldn't get a job until now, and this is the response I get. My friend says he's dumb and my mom says he's self centered. This definitely isn't the first time he's treated me this way, too.