Should i worry if he's not texting me back?

The last time i texted my boyfriend was friday and everything was okay.I was in the hospital for low potium and he said "get better i love you" and then i texted him that i was out on saturday.and he didn't text back.Then i texted him on sunday and i asked him if we could hang out on monday and he hasnt texted me back at all for 2 days. Should i worry?? Should i text him again today?? I really don't want too seem to clingy or despereate... (by the way were both 17 and we've been dating for 7 months)