i dont understand why you would be worried about if the job will take longer... or if you have priced it correctly.
think of it this was: if the job takes longer than planned, work harder next time and learn from it for other projects/contracts.
If your worried you have under priced a job, just remmeber in theory it actually costs us wated fed polers very little to do a job! so if its slightly under priced either bite the bullet or increase it! but most important never worry we have the best job in the world!!!!