'87 4kq: oil system question/emergency?

[Andrew Buc]

Today I did an oil change, pouring the new oil in from a 1-gallon jug. The jug
had one of those tinfoil/plastic/whatever seals on it (visible after removing
the cap). Long story short, a piece of the seal about 1" x 1/2" went in the oil
fill hole in the cam cover, and now I can't see it in there. Do I have a serious
problem here? I'm feeling a bit sheepish, but that's another discussion. TIA