D.W.
The first thing is the more you supplement the less milk you will make. You have to ditch the formula and breastfeed him if you want to be successful at breastfeeding.
Your production doesn't slow down after 6-8 weeks, your body adjusts to exactly what baby needs. That's what those first weeks are about. Baby nurses (sometimes erratically it will seem) to get you to make just the right amount.
Breastfeeding is about nursing on demand. Your body will adjust to baby sleeping at longer intervals so that you still make what baby needs. If baby starts sleeping longer at night they usually will nurse more often during the day. You might have thought him nursing more often meant you weren't making enough so you started supplementing. Common mistake. Now your body really isn't making enough because by not nursing as often you are telling your body it doesn't need to make the milk.
You need to ditch the bottles and the formula. Let baby bring your supply back up.
Now it sounds like he did exactly what he should have done this am. He emptied your breasts and was done. That's what breastfed babies do. They eat till they are full. With a bottle they eat till it's gone. See the difference.
If you want to increase supply put baby to breast every time and often right now. Breastmilk is metabolized more quickly so it's normal for him to want to nurse every 1 1/2 hour-3 hours. and that's from the time you start not the time your finish.
Check your area to see if there is a local breastfeeding support group. They can sit right with you and help you get him to latch on better. Try not to wait until he is starving to put him on either. Makes it more difficult to get a good latch. Watch his cues for hunger and put him to breast before he is ravenous.
Here is a great article with pics to get you going in the right latch direction:
http://www.askdrsears.com/html/2/T021000.asp
Most importantly be confident in your ability to feed your baby. Follow his lead and you will have the milk you need for him!