These stocks are all down 14% or more in the past three months. Many growth stocks have come under pressure recently as investors worry if their valuations are too high. But buying strong growth stocks after they've dipped in value could set you up for some great returns -- assuming, of course, that you're willing to be patient and wait for market conditions to improve. Three stocks that have been struggling of late but may be excellent long-term investments are Celsius Holdings (CELH 1.81%), Novo Nordisk ( ...