nervous about sex after 6 months

i’ve been dating this man for 6 months, and we had been friends for about a year before we started dating so i was already pretty comfortable around him when we started sleeping together. now he’s staying at my house 5 days a week and we have sex just about every day. and the sex is AMAZING every single time, but for some reason i get insanely nervous before every single time we have sex. i have a moment of instant panic when he initiates, and i have to mentally prepare myself for ten minutes when i want to initiate things. i WANT to have sex with him, i have a very high sex drive and i’ve never had this problem with any of my past partners, long-term or casual, and i’m worried he’s going to think i’m losing interest because i’m always so anxious before sex. does anyone have any idea of what could be causing this?? or any advice on how to navigate it?