I've got migraines, runny nose, watery ears, itchy throat, coughing and sneezing. Had it for 3 weeks. Is this a signs of something?

Hay fevers. You likely get an acute episode of allergic rhinosinusitis or previously known as hay fever. Depending how severe your symptoms are, you might need antibiotic and antiinflammatory medications if bacterial infections occur. Please see your local allergist for evaluation.