I don't really understand the wave-particle duality of light.I don't really understand the idea of photon, The idea of photon that is generally taught is that it is a fundamental unit of light with energy h$\nu$.But according to electromagnetic theory of light, rate of energy transfer per unit area is given by $\vec{S}=\frac{1}{\mu_0}\vec{E}\times\vec{B}$, and by substituting expressions for $\vec{E}$ as $E_0\sin(kx-\omega t)$ and similarly for other variables at some $x=x_0$(say 0) and by adjusting the area and integrating over a very small interval of time,the net energy transferred can come out to be less than the energy of a photon. What does this imply ? I have heard about the existence if single-photon emitters, what would happen if an interference experiment is conducted with them? Will there be a particular bright spot or what is going to happen?
The more I read about this, the more doubts I get. It would be really helpful if someone can explain the notion of a photon.