I'm doing a research for a report about this, and those dots are nothing to worry about. They're generally called oil glands and secretory cavities and its a diagnostic characteristics for that family. That means its one unique features of these plants. Basically it's the same stuff as the dots you find in an orange skin and pomelo skin. Which are related to lemons. They contain aromatic oils which is why if you squeeze it, it would spray tiny liquid particles in the air.
