Bottles do not make babies sleep longer, they just expand babies stomach and make them hungrier. It would be beneficial if you dropped the bottle to ensure that the stomach does not expand.
It is completely normal for baby to sleep and feed in the routine that you little on is feeding. That IS how they feed until the body is satisfied that the breasts have a good supply. it generally settles around 6-8weeks, and then sometime after that you realise baby is going longer between feeds. Maybe get a sling during the day so baby can feed whilst you do chores. Or for the evening so maybe settles better before bed time.
Another thing that helps mums in the early days is reading the UNICEF Safe Bed-sharing leaflet, if you tick all the right boxes then you can bed share (you sleep and baby feeds) without the risk of SIDS.
You milk is made specifically for your baby, it is specially tailored for your individual baby. It will be good enough. The first milk aka "liquid gold" is called colostrum and that is like a booster for the immune system, that can take any time up to 8 days to change to the white stuff, which in essence is the colostrum and then a 90% water volume added to it.
Trust in yourself and your baby. Everything is completely normal. But if ever you are in doubt look at baby's nappies... 6 wet nappies a day. And a poo that is mustard yellow in colour and porridge/chicken korma in texture. If that is not the case then, feed your breast-milk more often, keep offering until baby refuses (cannot force feed a breastfed baby and you cannot overfeed a breastfed baby - hormones prevent both of these - However you can overfeed and force feed a formula/bottle fed baby)
Remember feed to cues not cries and feed from one breast per feeding session - allow baby to come off them-self, do not assume because baby's eyes are closed that they are asleep, they are asleep when they spit you out. Some mum's do not realise this and then wonder why baby is waking up sooner, it is because mum is taking baby off before they are ready and before they have had the "sleeping tablet" at the end of the feed.