Id start Propecia now aswell.. results in a year... cant do any harm in trying it. But go for Proscar instead... cheaper, you cut it into 4 or five and it does exactly the same thing...
Be prepared to have to take Minoxidil for ever if you've started already. Id personally take proscar first... then add minoxidil down the track... i fully hate the stuff... especially having to look at my hairline in detail day in day out, whereas Proscar takes 2 seconds once a day and its piss easy.
Others on this forum will disagree about the minoxidil, thats fair enough as it works well for some, but just be prepared for the commitment... i wasn't, and im not just yet.