Is it possible to grade BPH after a finger exam?

Yes. A finger exam is a good way to detect the size of the prostate. It can also aid in the detection of prostate cancer. The best method to grade the prostate size, however, is by a transrectal ultrasound.
Most of the time. A digital (or finger) exam of the prostate can give a reasonable estimate of prostate size. However, some patients do have an enlarged median lobe that cannot be felt because it projests into the bladder. So some patients may benefit from measuring prostate size with an ultrasound.
Yes and no. A digital rectal exam will estimate the size of the prostate but keep in mind that size does not necessarily correlate directly with symptomatology. This is due to anatomic pathology beyond the scope of this space. I assume this question is not for you as BPH does not occur at age 34.Hope this answers your question.