L.C.
From my experience with both of my kids all this seems very normal. I think all kids are different and you just need to go with it. Both my kids only took 30 - 45 minute naps when they were young. As they got older they would get better at taking longer naps. My 9 month old will now do 1 45 minute nap in the morning and a longer nap in the afternoon. But when he was 4 months old it was just short naps and that is very normal.
If you are down to 2 feedings at 4 months old I think you are doing great and I would not worry about it at all. My 9 month old is still up once a night but that just happened recently, he was doing 2 feedings a night up to 8 months old I think.
Everything sounds VERY normal and it "will pass." Just give it some time. The crazy 3 year is normal too... I am there right now as well with my older one :)
Hang in there!