Downswings suck especially when you're moving up to a higher limit. You don't know if it's your play, b/c the games are harder, or just variance. I too beat the crap out of 1/2 and have had more limited success at 2/4 and 3/6. Focus on game selection and playing well. You will get through it. Just realize that the donks at 2/4 are the amse as aat 1/2 you just have to adjust to the better players.