OK, first of all, the vasovagal syncope can cause a lot of the same symptoms as seizures (I've got those as well as epilepsy, and the only way I know the difference is how I feel before hand- like with the weird chest feeling for both, although they are also different, as well as the 'tunnel vision' before passing out- I don't get that with the seizures).
A negative EEG doesn't mean no seizures, but just that they didn't 'catch' one during the EEG. The venous angioma may be causing seizures, as it's something that's not usually in the brain, and might cause pressure on parts of your brain, especially if you're anxious, and your blood pressure is likely up.
Tell your MD you need HIM to tell you what's going on so you understand it- it's hard to get evaluated for something and not have anyone really clear things up for you (had that last week myself, with an abnormal brain MRI....found info on the internet, and also a nurse friend near where I used to work).
The good news is that if they thought you had something horrible, you wouldn't have been allowed to go home, and would be going through every test in the book. You still might have tests in the future, but that doesn't mean you have something dreadful. And even if you do have seizures, at least it's an answer that has treatments......
Best of luck to you