Despite feeling "beat up" after winning "Celebrity Apprentice" last night, a resilient Bret Michaels was ready to party ... "sort of."

Michaels, who was hospitalized after suffering a warning stroke last week, hit up the finale after-party at the Trump SoHo in NYC -- where Bret said he was "so happy to be here."

Bret's $250,000 prize will benefit the American Diabetes Association.