Suffering With Recurring Blackouts, Instances Of Headache, Ringing Ears, Blindness For Few Minutes. Cause?

I am a 19 year old female and I have a weird question. I have seen several specialists and they have no idea what is wrong with me. One said it was seizures but had no evidence of it. For the past few years now I have been having "blackouts." I call them this because I haven't heard of anything like them before. They are brought on for no reason, although they have happened more frequently and gotten more severe since I had my son 8 months ago. They consist of me going blind in both eyes and sometimes I get a headache, my ears ring, and parts of my head go numb (most of the time in my mouth and ears). I do not pass out and can still move, talk, and have my eyes open (though I cannot see anything). One time I fell down and started twitching but it hasn't happened again since. What could this be!?