Help me

Okay so em and my bf are together for 7 months at start I really felt awesome he was the guy of my dream but lately I have some concerns I mean he is very good with me and respect me.But I think I have lost feelings or my love for him is not that's strong but idk like even now that I Wright this my gut is saying that I'm just overthinking...Idk what to do..Also throughout my relationship my bf is somehow jealous of my ex that is not realy my ex bc it was like a situationship.So my "ex" was not a really good guy he didn't really treated me well and when I understand that he is bad I left him and stopped texting him.After that I mer my bf but my ex still texted me and I didn't reply this went on for like 4 months after that I finally replied and told him to fuck off and ro leave me alone.But like he still watched my stories but I dint think anything then 2 months after that me and bf had sex and it was my first time but someone spread a rumor that me and my ex had sex so bc I didn't bleed my bf believer the rumor for like a sec and we argued but after a day we were okay..That day I conformed my ex and ask him if he was the that said it bc he doesn't really have a good reputation but he said no I didn't really believed him but I was tired to keep going so I left him on read.Now fast forward after 3 months he started watching my stories again and like 2 day ago he followed me agin and liked my pic and I know it is wrong but I followed him back...I told my bf that he followed me and he was like..okay I guess anyway after that I find myself thinking about him...and his name day(is like a birthday) is in 3 days so I'm thinking of texting him happy name day but I know its wrong and i won't do it but the thoughts are eating me ...why ate my feelings and my thoughts soo complicated?