I bought paint for ceiling from b q began by stirring the paint as normal and started painting ceiling with a new roller the paint does not go on as expected (flat and Smooth) But bubbles appear cannot seem to smooth these out I suspect paint is problem?
I think the problem is likely to be with the existing surface rather than the paint?
You will usually see bubbles appearing where the existing paint is not adhered sufficiently to to surface. This can be caused by damp or, more recently, because the surface wasn’t properly sealed before painting.
This is becoming quite an epidemic with new-build properties. If the problem is minor then you may find the bubbles will dry flat after a day or so? More severe bubbling may necessitate scraping the loose paint off the surface before going any further.
If the problem is isolated to a small area you can sometimes get away with using a brush rather than a roller as this causes less disturbance to the surface and less problems with bubbles.
All the best.