Erek
First and foremost congratulations, you have achieved a Partial Pass!
It is a pass and certainly not a fail, even though you may well be disappointed at not getting a full pass.
The IRT is not an easy test. It is made up of many fairly easy components but with the pressure on the day it is not difficult to mess up something and end up failing a section. I tell my students that in order to get a partial, they have got probably got 95% right. This would be a solid pass in any other type of game I know other than Russian Roulette!
OK. Now what? Make sure you have a very clear understanding of what you have failed. Sometimes the adrenalin on the day makes for selective hearing at the examiner's debrief. If in any doubt, ask your instructor to telephone the examiner. Next, book an afternoon test and fly in the morning with your instructor and practice until you can do it perfectly. Go straight off to test and clear off your Partial. Next go off and celebrate your success. When in due course you have recovered from the inevitable hangover, please let us all know here at PPRUNE!!
Lastly, a small ps. I know of several airline training managers who didn't get a full pass on their first attempt at their IR. You are not alone, it is no disgrace and it is not a blight on your career.
Good Luck