So now that your kid is 5 years old, he has started developing the quality to think on his own without much assistance and decide what is right and what is wrong for him. At this age, kids might have to deal with pressure sometimes whether it is related to their studies or any other aspects.
What you need to know
Let them deal with their presure on their own as long as they do not ask for your help. This will help them in coming out of their problems on their own and they will become more decisive when stuck under pressure of resolving something important.
Children of this age develop the ability to stay calm under pressure as their thinking level is not as mature as of adults. So even if they are under pressure they will deal with it as if nothing has happened and they will handle it very calmly.
Children do not hit the panic button like adults and this quality of being calm that is developed in them naturally should be supported by the parents and given a boost. If the parents will set an example for the kid by staying calm and cool in certain stressful situations then the kids will adapt that quality too.