Is it normal for me to get so worried all the time?

Okay, so, I've been going out with my amazing boyfriend for nearly a year, we are both 17 & tbh, I can see myself with him a few years down the line. We are both relationship people & in love. However, I worry. All the time. If he doesn't text back, if he seems a bit off, if we argue etc. I read way too far into things. We don't text & talk 24/7, he says that he prefers to wait till I'm home from school & talk to me on the computer, he dropped out of his course because he didn't like it, anyway, he says that because he thinks it's better to have something to talk about when we do get chance too, like asking eachother how our days were. Is it okay to not talk to your boyfriend ALL THE TIME? & also, we have wee arguments because I'm really stupid & worry about things that aren't even there, like today, he was playing a game on the computer & I was chatting to him, he seemed a bit off & I automatically worried that he didn't want to talk to me, when I know it's the complete opposite & I try to tell myself this all the time. Also, I've been quite down lately, due to personal reasons & sometimes I get frustrated & take it out on him, accidentally of course & we have a wee argument, which I then feel terrible for an apologise for continuously for days after, for some reason hen he says that everything is okay but I still worry that it's not. Please help ): I worry all the time when I don't need too D: he says he's never going to give up on me, but I can't keep feeling like this, but I can't lose him.. He does nothing wrong, it's all in my head, please help ):