Oh ok, so he's waking at night putting everything in his mouth. Breast fed and I really don't want to start now, if that makes sense. He's not doing any of the more advanced stuff you mentioned lulumama
Wanting to keep exclusively BF your baby at 17 weeks is just the right thing to do :-)
The real signs are the sitting well unassisted and being able to bring food to their mouths. DS started weaning at 23 weeks when he could sit happily in his highchair, take some brocolli out of my hand and eat it :-)
I weaned at 19/20 weeks but to be honest I feel I held out as long as I could and think he was ready a couple of weeks earlier.
and when I did offer some baby rice, he gobbled it up the HV said she he might only take 1/2 spoonfuls the first time so I only made up a tiny amount of baby rice and then had to make up more because he was grabbing the spoon and shoving it into his mouth.