Home Brewing: First brew complete, on to the tasting and next brew!

Well, 1 month has passed as of yesterday since i made my first brew. I made a Cincinnati Pale Ale. So i got home, put it in the fridge, and started on my next brew.

I opened the beer. Sounds like beer!
I poured the beer. Looks like beer!
I tasted the beer. Tastes like beer!

It had a really good head on it when i poured. The clarity is what i expect for a pale ale. A good amber color, not too hazy. It had a slightly hoppy aroma and it taste great. According to the recipe, it should have resembled Sierra Nevada Pale Ale. Well, it kind of did. It was hoppy but had a clean taste to it. The only thing i noticed from first taste, was that it lacked a bit of a bite after. I was afraid when i carb'd it that i wouldn't have enough carbonation. Though when i poured i had bubbles coming up through the whole beer. But by the time i was finishing my 2nd beer, i didn't notice any off flavors at all.

So overall, i think i did a pretty damn good job.

I also brewed a porter last night. Steeped the grains, then added the extract and started boiling. Well, i didn't pay attention because i was getting stuff in the house. Came back out, and my fire on my burner was out. So i looked around. I had a boilover. My heat was up way too high, and it boiled over, so i relit. Let it go, then the burner started catching on fire. I killed the heat took off the pot, and had to scrape gunk off the burner. Put pot back on. And continued brewing as normal.

I realized this brew, that the heat did not need to be fully cranked, i had it set pretty low, and had a nice rolling boil all the way through and had no boil overs from hop additions.

Once i was done i started cooling, well... i had a Wyeast london ale slap pack, i slapped the pack and then read the back, didn't know i was supposed to wait 3 hours.
So i just continued on, and pitched an hour later.

My porter is fermenting now. Last night i had a good head going on, but i look this morning, and the foam is starting to subside. I'm using my freezer with my johnson digital temp controller. I'm having problems.

I have my setpoint at 65 (suggested fermentation temperature) and my differential on 3 degrees. Well, after i checked it again, the temp last night, it was at 59. Apparently the freezer is kicking on and when it shuts off the temp drops too low. How do i set my temp controller right? Should i set my differential lower, to 1 degree? I don't believe i quite understand what the differential does.