Wish it was that quick! Going thru all 36 locks on the Erie Canal took us about a week.
The Welland Canal is much shorter, however, you have to bide your time waiting for an opening for a recreational vessel.
It took us 4 or 5 days to go from Buffalo to Oswego on the Erie Canal. Your trip for the whole canal is about right.
Downbound is always easier. As the water drains from the middle of the bottom of the lock it tends to pull you away from the lock walls. Upbound is more challenging as the water comes up from the middle and flows towards the lock walls, pushing the boat towards the walls.
One big difference, besides the size of the locks, between the Erie and Welland is the dominant traffic. The Erie is almost all recreational whereas the Welland is almost all commercial. The lock masters on the Erie really work well with boaters slowing the water flow to make it easier to lock through.