bubbling is not necessarily indicative of fermentation. however, your fermentation temperature is quite high so its likely over. check your gravity at 7 & 10 days, if it hasn't changed you're good to go.
28 Celsius is HOT. Unless you were finishing up a saison, that's about 8 degrees (C) too warm. Most yeast strains would ferment out, sometimes explosively, at 28C. Next time, keep it at 20C and the beer will be better for it.