Don't be negative and (always) look on the bright side (of life etc.).
I think you have 3 chances at least (and even more):
1- Start now. Go to gym, swim every morning, from 6 am to 9 am.
Let your muscles grow jogging. Eat many proteins, rice, no fats, no smoking. On april the 3rd, you'll be ready to leave USA towards Europe. Some good swimming and then a long walk. I can assure you that you'll reach Wacken on time. What I _can't_ assure you is that you'll find the force to see the concert, but it's not important.
2. Reach New York. New York-London is something like 5-600 euros, if you book it in june or such. Then London-Berlin by Go! (or Eurolines bus), then Berlin-Wacken by bus, but I'm not sure about the prices.
It shouls be around 1100 euros maybe.
3. Find a rich widow to pay your bills. Never say never.
And the best luck
a/v