I wish Aidan slept that long. But sleeping through the night at this stage is actually 5 hours. If you get that or more, that's fantastic. Aidan usually sleeps about 4 hours, sometimes closer to 5 with his first sleep. Then he sleeps 1.5hr, 1.5hrs. Although he sometimes has a very wakeful period in the middle of the night after his long sleep. He'll then sleep for 3-4 hours in the morning after breakfast and playtime.
We are going through a screaming period right now that starts around 16.00 and goes until he goes to bed. He wants to be over your shoulder with you standing. I think it's his teething as even that doesn't work at time. We've used out office chair and spin in that, which he likes. We go through a cycle of distracting him.