The finale's on May 17th. There hasn't been a s14 confirmation yet, but if there isn't to be one then I'll be astonished. If this were the last season every promo would already be hyping it as such. There's no reason for the network to do an out-of-the-blue cancellation. If WS does get picked up, the PTB will want SPN around at least for another season as a lead-in and so they can do a crossover or two.