I have no idea. But I think you made your decision, given all the information at the time that you had, so it's pointless complaining that you were misled. The only way that could have happened is if she didn't tell you until you were actually in the act and went WHOA WTF IS THAT??? But she tried to tell you. She probably didn't expect it would go as far as it did, but once it did she did what I would consider the decent thing and "warned" you. As I said, nobody forced you to do what you did. You could have said that changes everything sorry I have to go, or made some excuse --- hell, you could have thrown her out/walked out and I'd have more respect for you.
What you did was: you had sex, KNOWING what she was. NOW you feel bad, wish you hadn't, but refuse to take the responsibility, saying she led you on, she lied to you. What utter tosh. You knew the score but wanted your end away and now you can't face what you've done (in which there is, by the way, nothing wrong) and want to find excuses and someone to blame. AND you haven't the balls (or hadn't: I see you say you just texted her, interested to see how that was taken) to text her and explain what were your pretty reprehensible actions afterwards.
You know, thinking about it now, I probably, almost certainly would not go to bed with a "chick with a d1ck" as they say. I'm not gay and to me sleeping with a TS/TG/TV whatever would probably still fall into that category. But I'd have the decency to say no thanks and leave it at that. You didn't do that. You wanted to have your cake and eat it (could there be a worse or more double-entendre-prone metaphor?)
