Awww, no he loves you!
I use a Mendota british style slip lead. I was told to not use a harness until they perfect walking with a regular collar because the harness is what makes them use more of their strength. Then for puppy class we had to use buckle collars and leads (no harnesses). Herman will be 6 months soon an I still havent gotten his harness yet, and he loves every dog and every person too. So when I go to the park, I use the buckle collar so he can play with people/dogs without getting choked. When just walking to go potty I use the Mendota (I have the 4' one and 6' one). Don't use a retractable leash, instead get a shorter leash for "get it done and go home walks" to keep him close to you.
And yes, my dog is strong too - bullies can be stubborn and will move when they are ready, and it's like trying to move a wall! Your dog is just very sociable