No it would be schizophrenia, but the difference between a hallucination and a real spirit voice is that the real voice tells you facts .
Not necessarily (in either direction).
I was told by a female voice that I would win the lottery one hour before I did win five numbers.
There are a few problems with this as supporting evidence for this spirit world hypothesis.
1. We have no reason to believe that this happened as you described. Even if we assume you are being entirely truthful with us (which is what we normally do assume here, unless there is substantial contrary evidence), there is still no reason to believe that this happened as you describe.
Here are two rather lengthy lists of the problems with human memory and reasoning, and why we simply do not trust them with anything but the most mundane of tasks.
http://en.wikipedia.org/wiki/List_of_memory_biases
http://en.wikipedia.org/wiki/List_of_cognitive_biases
2. The spirit world, were it to exist, could not possibly interact with us in the way you suggest.
3. Winning a middling prize on the lottery is hardly unusual or indicative of anything else unusual. My parents were in an office pool that won first prize in a lottery a couple of years before I was born. There are lots of lotteries, and lots of people win them. Lots of people think they are going to win the lottery. Some of the people who think they are going to win the lottery are the same people as those who do win the lottery. This is known as a coincidence. Literally, because it's where the two sets of people coincide.
I have done the lottery since it started and I still do it and the only time I heard a voice say I had won was when I did win.
See those lists above? You need to rule out every single one of those problems, and it's not actually possible for you to do that.
The odds against a five number win are 55000 to 1 and the odds against hearing a voice tell you you are going to win the only time you did win must be astronomical.
Littlewood's Law states that people experience, on average, one miracle per month, where a miracle is defined as an event with odds of 1 million to 1 or greater. Minor lottery prizes are common. Auditory hallucinations are common. Cognitive and memory biases are universal. And your hypothesis of communications with the spirit world is known
a priori to be false.
So, this is where all this leaves us: We accept that you won a prize in the lottery. We accept that you are being truthful and that you remember a voice telling you that you were going to win, that one time out of all the times you entered the lottery. And this is completely worthless as evidence for your belief in a spirit world, which we know to be false.