insecurity

my boyfriend and i been together for 4 months were moving really fast we try to move in together but it didn’t work we feel to comfortable, cozy and become lazy we dont bound anymore, s3x life was affected, he wanted to move out to have his own space and to be an individual, which i was having a hard time to understand bc i was happy and excited living together, and april fools day he prank me saying he ask someone else phone number but it was dominos but it gets into my head and i feel fear and paranoid that he might be bored of me he might nit attracted to me anymore he reassured me but why do i still have this fear 🥺🥺 i need advice and help