Sexual abuse

A friend of mine just told me that she was abused as a child,in reaction to this a few things have been happening to me that I am surprised at.
1:when she told me i felt sick and have spent the past 48 hrs since feeling this way,i also cant stop crying everytime i think about it. I have other close friends who have also been abused in this way but only with this current friend have I reacted in this manner.
2:A few memories from my childhood seem to have literally cropped up in my mind.It should also be noted that i cannot remember most of my childhood and it is as if it did not happen, yet there are a few things i can rememeber.
3:I started masturbating at a very young age, we're talking 5-6.
4:I remember acting out sexual fantasies at the same age,these fantasies would involve my self and a church audience.
5:I remember walking into my mum late at night in our living room, I think I would have been 7ish, she was there with friends, no males, and just bursting into tears.I dont know why.
6:I never liked being left alone with my dad,not out of fear,i just didnt like it.
7:I remember speaking graphically with a friend about the male penis, at age 8/9.Yet my knowledge of the female organs was practically non-existant.
8:I told childhood stories to friends that usually involved my fathers penis, I would have been 8.
9:At my current age(18)I have been in therapy for self-harm, anorexia, bulemia and agoraphobia.I have huge trust issues in all my relationships and have some sexual problems such as discomfort during penetration and a low sex drive.
10:My sexuality is also an issue to me as I believe I may not be straight, but in fact lesbian.
11:I still do not like being in a room with my dad and always feel he is looking at me. I have also caught him staring through my bedroom door-blinds,watching porn and I have a vague memory of him catching me masturbating.
12:I place little value on sex and have acted too quickly on occasions, something which I am ashamed of.

The reason I had to tell someone about this is because I believe I may have been sexually abused as a young, young child. I have no memories of this abuse but in my head I feel like I know that I have been.I would like a personal opinion on this as I feel I must know, or atleast be advised to whether I was sexually abused or whether I just had a very warped childhood. If there is a chance I have been and have repressed a memory, I need to know.

I would greatly appreciate a response.