Life can be stressful and we make plans, and more plans, and more plans but find we are still subject to the powers of fate. Goal setting and daily objectives is a great way to get ahead; research supports their utility in long term success. Keeping focus on each day helps to reduce the stress from all the "what ifs". Plan and move on.
Planning for life and emergencies is helpful. We plan for our futures, make vacation plans, project plans and strategic plans. We can even make contingency plans where X or Y will receive response M and Z. If four factors are together then we can have option S over F.
Highly developed strategic planners can make contingency upon contingency and have an entire operating system mapped out. The only problem is that sometimes life throws curve balls by bringing in unknown factors in combinations few could foresee. In such cases you just have to deal with it.
Make reasonable plans and then live each day like it is your last day. If you have the mind of a strategist then make a few alternative back up plans and then start living those plans. Focus on putting one foot in front of the other and on things that happen each day while temporarily not worrying about unknown futures.
Be confident in your skills to handle these unknowns when they occur. Planning reduces these fires but one must still be in the present to reduce the cognitive load associated with calculating and recalculating. Stress is beneficial for motivation and getting over small events but can be difficult over the long run.