Am I being selfish??😩

Long story short.. my partner has a 6 year old boy.. I knew this for years (as was friends for 4 years before being together) I love children been around them all my life.. having his son every weekend was never a problem I’d make sure it was amazing every weekend he come over. Then the ex come along and started texting more often and I told him ‘she misses you’ he obviously didn’t believe me.. so I just sat and waiting for the day she told him..and obviously she did.. I wasn’t threatened by her in anyway I knew he didn’t want her but it still knocked me a bit and I did worry.. I got over that then not long after I had an ectopic pregnancy 😔 after I was fine with still being around his son and doing things together, but now I feel I don’t want to be.. not that I can’t be, I don’t want to be.. and every weekend having the son is getting to me.. I want to have more time on the weekends with him ( as that’s the only time we have to do anything as we both work Monday to Friday ) and I’m kind of unhappy he has a child with someone else now.. I want it more now it was taken from me but I know my child won’t have the full attention and that hurts a little. I do think I’m being quite selfish about the whole thing but I just want my child to have all the love from it’s dad when the time is right.. hearing someone else call him dad hurts me sometimes..😔 I know it’s not his sons fault and not once have I made any of this obvious to any of them.. does anyone think I’m being seriously childish and inconvenient?