My kitchen sink spray was working all right, plenty of pressure until I had a new faucet installed.

The faucet has pressure (as before the change) but when I use the sprayer it goes down to almost a trickle. Before the change the faucet and sprayer had good pressure, now, only the sprayer has lost pressure?

Can someone tell me where to look? What should I check? Is it possible that the hose under the sink is too long? I don't want this plumber (and I use that term loosely) back and I would like to see if I can find and fix it myself. By the way, I only replaced the old one because it was old and dated, it still worked fine.

Lost in the desert..