Nobody can say if you suffered a concussion from your description. It does not sound like you have the symptoms of a concussion.

The wee bit of pain suggests a mild contact. As I have commented many times, The skin over the skull have many layers that are full of nerve endings that can easily be traumatized without an impact that is of a concussive level.

The stiff neck suggests it may be the cause of your headache.

If you are a habitual neck cracker, you may be developing some arthritic like issues.

If you were drinking enough to not pay attention, that suggests it was too much for a PCS brain and also enough to put you at risk of falling or antagonizing another attacker.