If you successfully attend and pass a project week, you should see the grade in Osiris as 1. Similarly if you pass 2 project weeks, you will see a grade of 2. If you attended 3 project weeks and you do not see it graded as 3 then that means that you failed your third project week.
You should also refer to the comments given by the Project Week supervisor in your report submitted in the TurnitIn area as they give you a clarity if you have been passed or failed.
Please note that you are not given a grade but rather a count of how many project weeks you have passed.