The first 6 weeks with a new baby is really tough (you have a couple of weeks to go yet). But, I have to tell you honestly, excusively breastfeeding is not the solution if you had planned on giving your child breastmilk for any length of time. And you can sort out the breastfeeding. It will get a whole lot better, and quicker than you think.
Right now, like most mothers, you probably have a relative oversupply for your baby's needs. Your milk supply is driven by your hormones - prolactin, in particular, which is at a high level now. Over the next few weeks your prolactin levels will go down to a fairly low/normal level - but your milk supply will be controlled by your baby's sucking. To be honest, 4 pumpings a day will not cut it. And your milk supply will gradually reduce. Babies are designed to feed 8-12 times in 24 hours, but few of us will use the pump 12 times in 24 hours.
In the long run most of us who have had a baby and a toddler find that breastfeeding is easier - you have a spare hand for a start.
What you might find helpful if you haven't tried it yet is *block feeding* - your baby feeds as often as he wants in a 4 hour period - but from the same breast (then swap after 3-4 hours) Your other breast will get very full. If it is uncomfortably full, express a little off to ease the pressure. The rationale - baby can feed as often as needs, but the breast will be relatively emptier. So he will get a smaller quantitiy of milk which is higher in fat (keeps in satisfied) but lower in lactose and volume. Many mothers find it helps.
Exclusive expressing is a solution in a situation where a baby is not able to feed directly at the breast - but it's a last resort.