I have had some similar concerns, but have decided that worrying is not worth my time and energy. My baby is 6.31kg as of today and he is 6 1/2 months, I had issues with him waking every 2 hrs overnight to feed, things have improved since he had his tounge tie corrected and I started him on solids, he now only wakes once or twice.

I decided that my baby is happy, is now sleeping well, hitting milestones on time and gaining an average of 80gm week. He is quite active and has a great appitite. DH was a small baby, though DS2 is smaller I have decided that he is just going to be small child, that it is genetic and not going to worry any more.

It sounds like your baby is happy and healthy, introducing solids wouldn't do any harm, we r doing a combination of BLS and purees, it worked well for DS1. DS2 had a ball yest squishing a banana.