Messaging

So i made this account because I can stop worrying and hopefully you guys can settle my mind a bit. Ive been texting a guy for a few weeks now, we've gone on two dates and hit it off great. Theres some distance between us, about an hour drive and i dont have a car so I rely on him for the transportation. We arent dating yet but I plan on asking him within the next week. Heres the problem in my head, within the past few days ill message him and get no response. He then texts later at night and we talk back and forth for about 30 mins but then he just goes silent. Is there a reason i should be worried about this or should i just assume he's busy? I would tell him goodnight and usually get a response but nothing in the past few days. When we do message each other, hes the sweetest thing and calls me the nicest names ever. Hes already so supportive of me even though we arent together. My mind loves to assume the worst situation possible and i always think that the person im talking to will just throw me away so I'd like to see if im just over-reacting like usual. Thanks guys! .^