Not going to make much comment on the original question as i believe the the PP have said everything that i would add to these comments... other than, look into BLS - if you think that your baby is ready to eat, hand them the food themselves, they will only be able to consume what they are ready to eat - which at 6 mths is not much at all

On the contrary I'm considering (not yet deciding) introducing solids because I want to be able to sleep. I'm so tired I've been sick and cannot function very well lately.

With my first baby I didn't start introducing solids until she was 6 months old, and it was fine then because I had abundant milk. It seems now my milk supply has been compromised by lacking of rest during the day for looking after my 4 year-old, though she goes to preschool 3 times a week I still feel very tired.
Lady Noor - did you find that your fist baby slept better after solids? I didnt... and i dont know loads of people that did notice a great increase in sleep or any at all!
I would be exceptionally hesitant to start solids early based on this reason alone.