hi, i dont know what happens with regards to re-sitting exams etc but just wanted to say -you WILL pass! Im guessing you have your exam coming up as i was feeling like that before mine and couldnt sleep due to the worry of failing!
Best thing i can tell you is to try and relax, and when you have the exam try and put it out of your mind that its actually an exam! Keep telling yourself that its just the same as any other time you've done practical.
You will be fine, Good luck x