Nipple confusion

My baby is 7 weeks old and stayed in NICU when he was around 3 days old for 2 weeks and after he’s discharged he’s having nipple confusion according to a breastfeeding counselor and she gave me tips like feeding him with a spoon but honestly I tried for couples of times then stopped as I couldn’t tolerate seeing him crying his heart out plus it affected me mentally as I’m having PTSD from his birth

Anyhow now I’m pumping whenever I can and formula feeding him

But till now I feel guilty I have NO IDEA WHY!!

Plus I keep thinking a lot and worrying about his immunity plus losing the bond of nursing.

So plz reassure me from your experiences that your kids’ immunity are fine plus that they love you

Because till now I feel that he is not that attached to me 💔

Sorry for the long post but really The previous events made me too emotional 😢