Clingy 8 month old

This past week has sucked! My once great self settler who didn't care where he slept (his bed, our bed, pram, car etc) has suddenly decided he must be with me always. he'll be so close to sleeping and I put him down and his eyes shoot open and he cries within seconds, I pick him up and he falls asleep. Put him down and it repeats. He'll only sleep in our bed at the moment which isn't wha

t he usually does. It's like he is scared I'll abandon him! I've never let him CIO, I always wait until he's tired then put him down and he just goes to sleep. He doesn't stay with others or go to daycare so I don't know where this sudden fear came from! He follows me around crying going "mumumummum" until I hold him, then he smiles. He's a really good baby but I don't know what to do. Do I just give him the attention he needs? Is this just a phase? What have I done wrong lol? Help!