hit a rough patch with my partner (18m) and its destroying me (18f) HELP!!

my partner and i have been dating for just over 5 months and i love him so so much but there's been such a dramatic shift in feelings that i can barely describe

everything was fine like, 3-4 days ago i seriously don't know what happened or how to fix it

i get irritated with him quickly, i don't miss him nearly as much as i did, i haven't wanted to have sex with him since 5 days ago, WHAT IS HAPPENING??

it almost feels like im falling out of love with him but i can't imagine a life without him, thinking about breaking up makes me cry

someone please help me i want this to work so badly

tldr; feel like im falling out of love with my boyfriend