Just start back up tomorrow with your usual dosage. There shouldn't be any problems. The worst that can happen is you may experience a return of some hypo symptoms, but they should go away rather quickly once you are back on schedule. If you are to have thyroid blood work before 6 weeks, just let your doctor know that you were off your meds for 5 days.
You should start your medication again, and then remain on the schedule you were on previously. If you didn't have problems starting the medication, you shouldn't have any problems starting back up.
My question is I left for a couple of days on vacation 5 days to be exact, I forgot my synthroid so I have been of it for 5 days should I just start tomorrow. Or will something bad happen?