Feeling distant

My (20f) bf (20m) is currently on on a tdy and rn our schedules are flip flopped and we are in a LDR so rn our chats basically are goodmorning and goodnight with a little talking in between when possible. Ive been kinda bothered because ill be asking all these questions like " oh how was work" and hell respond but just not ask back. And ik its not that big of a deal but the small things matter for me. He hasnt asked how ive been or what ive been doing and its bothing me because it feels like loss of interest in a way? Ive sent voice memos saying that i miss him and im thinking of him and i hope works okay, but he just doesnt really reciprocate it back. And before this we were super lovey dovey and wed call everyday play video games amd ect. And im not really enjoying the feeling tbh and ik hes busy and i dont expect him to respond 24/7 but im getting nothing and its bringing me down. Its been 4 days. Can someone tell me if this is just like a quiet part of our relationship because the schedule is flopped and im kinda over reacting orrrr is it something i should say/ mention is bothering me.