For a self check, you can feel within your vaginal opening for a soft, round bulge.  For a more concrete diagnosis, I would recommend you see your physician or urogynocolgist.  They should be able to test you either lying on your back and having you bear down or while performing a wide leg squat to feel if you have a cystocele (bladder prolapse) and if you do, what degree it is.  Keep in mind that you should always work to strengthen the muscles of your pelvic floor even when you have had surgery.  As an analogy:  if you were a knee patient and went in for a menisectomy, you would want to do lower extremity strengthening exercises after surgery to regain a normal gait pattern.  If you don't, you may forever walk with a limp even  though the surgery took care of the torn piece of cartilage.  Your pelvic floor is a muscular area, so your approach should be no different.  Even with surgery to better support your bladder, you want to work through a pelvic floor strengthening program with a women's health physical therapist following surgery to improve your surgical outcome.