Co sleeping

So baby boy is almost three weeks old and he sleeps in bassinet next to our bed.But last two nights I would put him in bassinet later take him to fed and I would wake up with him next to me and I have no idea how I didn’t put him back into bassinet.

He is fine I would be on my side sleeping next to him and he sleeps to peacefully nothing happens to him.

And we both got nice sleep but when he is in bassinet he would be so fussy.But now he would sleep on my chest but if I put him into bassinet he will cry immediately.

And I don’t want to co sleep again.

How to deal with this