When my face is irritated, it develops tiny bumps all over, starting at the sides of my nose. The skin reddens easily in the areas. What's going on?

Rosacea. Typical signs and symptoms of rosacea include facial flushing, blushing, redness, burning, red bumps, and small cysts. The symptoms tend to come and go. The skin may be clear for weeks, months, or years and then erupt again.