The noise it made on startup bothers me a lot! Then you mentioned some seal stop leak you applied that same day.. Now that has me going real good!!
My first guess is you have a mess in there. I am not familiar with whatever it was you poured in your crankcase but I never would've!
If it is a rear main seal leaking I'd be checking my pcv valve and fixing the internal pressure before installing a new seal.
Right off I think I would drain the oil out and install a new filter and some oil with a can of "cleaner" in there too. I'd be running her at temp for 30 minutes and then drain her and refill with oil and a NEW filter.
Then I'd drive her and see what I've got.
Big JIm <img src="/forums/images/graemlins/pfft.gif" alt="" />