About a week ago I brewed up a brown ale that came to a OG of 1.070 and just tossed in a smack pack that I smacked 4 hours or so ahead of time. Its been 7 days and i'm almost at FG but i'm starting to regret the no starter. What do you think?
Your beer is fine. You underpitched, but it will still taste great. I read studies on underpitching vs. proper pitching and the results were not as cut and dry as you would think.
That said, a starter is a wise decision. Especially for a 1.07 beer. Usually a beer over 1.06 you would want a starter or two vials/smack packs. But your beer has fermented out so I don't see a reason to get bummed out if you didn't.
Take a sample and taste it. If it seems like it has some off or undesirable flavors from underpitching then let it warm up a bit and continue fermenting. Either way leave it in the primary for another 2 weeks if you can hold out.