Welcome to SR Catchment,
...The entire day, while I may think about drinking several times, I never really want to do it....
....I usually find myself driving to the gas station to get a six pack...
....Beer (which is all I ever drink) had always calmed me down and made me happy, but last night I felt like a completely different person.....
Yes, these parts of your story sound familiar. I was in my end twenties when I quit- and I wish I would have asked myself these questions honestly when I was 22.
What I experienced from a similar point than the one you are desribing is: it is very likely that your drinking will escalate. It is very likely that you won't stay functional. The "staying functional" aspect and the fact that I could sometimes go without for some time was what kept me in denial for a long time.
In the end, alcohol wasn't working anymore for me. Its mood altering effects were coming at me with a revenge. It didn't make me feel relaxed, happy and numbed anymore- it opened the floodgates for depression and anxiety. At times, it would make me feel angry too. And at the end, drinking started to affect my short term memory and other cognitive abilities. It was that emotional despair and how drinking made me feel that made me realize I couldn't live like this anymore.