Is this normal for couples??

My bf and I have always had sex every 1-2 or 3 days. Obviously once in a while we will only do it once a week but we shortly get back to normal right after. About 3 weeks ago we literally had sex for a week straight (which has never happened within the 4 years we’ve been together!) and it was amazing! The weeks after that kinda went downhill, we’ve been doing it maybe once every 5-7 days. It’s sucks but recently we just got back to normal and I’m worried it won’t last long ? Also, my bf is trying the “no fap challenge” 🙄 He would always tell me him masturbating helps keep him in the mood for sex so now I’m not sure if it’ll change !? He’s doing this for benefits such as more testosterone, better sex, higher sex drive, and more energy. BUT I haven’t really seen any change and it’s been a 1 1/2 weeks so far. I ALWAYS overthink about the sex part of our relationship even though I KNOW it’s not the main reason we’re together...I guess I just want to know if this is normal for couples???