Can you lose marks for over explaining answers?

I just finished my Cambridge Technicals in ICT and after a large amount of hard work and probably an even bigger amount of unnecessary exam stress I have completed it.

However, I’m slightly worried that I’m going to lose marks for over explaining my answers. For example, one of the questions was something like “explain why the extranet could be used” (3 marks) and I went ahead overexplained it, talked about other possible options, characteristics, etc.
Obviously as it is only 3 marks I don’t need to go over all this, but I was paranoid I would miss a mark by not showing the exam marker my knowledge.

Other than wasting time in the exam, are there any negatives to this when getting your exam marked? As long as I hit the marks and kept the information relevant to the question, would it negatively impact my exam results?

I was able to use a laptop which allowed me to add extra information without too much exam time being wasted.

I’m probably just paranoid, but it would be nice to get some confirmation.

Thanks

As long as you directly answered the question then you'll get marks for it. Anything that is not relevant to the question will not be marked.

Next time, try to be short and concise with your answers. It is going to make the examiner's job easier, because it would be easier for the examiner to look for the marking points within your paragraph and there's less chance that he'd miss the marking points.