When I pull the lever

Question

When I pull the lever to make an espresso it takes about 10 seconds for water to come out. It's as though all the water in the boiler (or heat exchanger?) drains out when I dont use the machine for about 20 minutes. I have noticed that it drips a bit out of the bottom of the group head. Maybe there is a leak in the discharge valve causing the water to leak out? I really am not sure what is going on with it.