Dreams about exams often reflect our anxieties, challenges, or feelings of assessment in our waking life. In your case, the dream seems to capture your current concerns regarding your real-life exam results. Here are some interpretations of key elements in your dream:

1. Doing Well Initially: The fact that you were performing well on advanced formulae suggests that you feel prepared and capable in your studies or skills. This indicates a level of confidence regarding your abilities.
2. Interruption by Your Mum: Your mother calling you for help could symbolize responsibilities or distractions in your life. It may reflect your desire to assist others or the balance you try to maintain between personal commitments and your own goals.
3. Achieving an Intermediate Level: The shift from doing well to receiving an intermediate level of achievement could represent your fears or doubts about not meeting your own expectations or the standards you feel are required. It can also symbolize a fear of not achieving the success you desire.
4. Crying and Credits: Crying in the dream suggests a release of tension or anxiety. Even though you achieved credits, the dream reflects a conflict between your hopes and the reality of your situation, especially if you believe you need to pass to obtain those credits.

Overall, this dream seems to echo your current feelings about the exam you took and your anxieties surrounding the results. While dreams do not predict outcomes, they can help you process your emotions.

Regarding whether you will pass, it's important to remain hopeful and focus on the hard work you put into preparing. Trust in your abilities, and try to manage any anxiety as you await your results. Good luck!