I'm sorry you are feeling so down about this situation but please remember YOU ARE NOT ALONE and IT DOES GET BETTER.
I have been through what sounds like a very similar situation myself and have done tons of reading and seen heaps of professionals about it. Finally more than 2 years and 2 babies down the track I am nearly symptom free.
I too had a difficult posterior birth with forceps (a major factor in damage to pelvic floor). I was diagnosed with cystocele and rectocele (GP said "severe" but months later it was assessed as "very mild" so remember this can change too).
From my reading and own experience I'd say the following:
Three months post baby is very early days - your hormones are still affecting your muscles especially if you are breastfeeding, which means your pelvic floor is quite weak and can't hold up your organs as well as usual. I did not start to have symptom free days until 12 months after birth.
New research is coming out showing MOST women who have had a vaginal birth have some sort of prolapse. Many have no symptoms and others are too ashamed to report it.
Seeing a GOOD physio who knows a lot about post natal issues is essential. Get working on your kegels and make sure you are doing them correctly. Strengthening your core muscles is important too (Pilates is ideal).
Get your physio to check to make sure your musculo skeletal system is supporting you well (I had a twisted pelvis from the birth and once the physio had treated this my symptoms improved out of sight!)
It is a real shock to discover but please know it gets better with LOTS of work and professional help.
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