If that is the only cheese you got out of 4 gallons of milk, you aren't getting the curds.
Something in the coagulation or cutting, or straining isn't there. Mine are 8" and 2 or 3 times thicker than your wheel, and they are all made from 3.5+ gallons.
From what I did, you will want to dry that Havarti. Give the exterior an olive oil/salt mixture rub to keep molds from growing for a few days as it dries of a draining mat. You'll be getting a fair amount of water/oil from the cheese for at least 5 more days. After that you can probably wax it. I waxed my two havartis after 7/9 days and they could have been done earlier I believe, but it didn't hurt to dry a little more.
It was tough keeping the rind mold free without a salt solution. After molds were dotting it, I applied olive oil/salt and it stopped any growth before I got to waxing which should stop it all dead.