I wanted to study something that I know for certain is the truth.
Might I suggest bricklaying, or carpentry? Seriously though, I don't recommend anything scientific if you want certain truth. How about becoming an artist?
Silly reasons, but it was long time ago, it doesnt even matter anymore.
The first reason was silly, but the others aren't.
I considered many, but some that I didnt exclude completely; math, and (dont know how you say in usa) electrotechnics/computer science.
That would probably be electrical engineering.
What draws me to computers is the idea that i could probably earn money with least effort because of my math skills. and it is "safe", you just do what you have to do and you know you're fine. unlike psychology where you can fuck up with someones head if you have a bad day and there is no black/white answers. (a part of math that i like the most is that you are either right or wrong and you dont need to worry that it depends on your performance if you have right answers - if i explained it correctly.. nobody can tell you you're a bad mathematician if you have results. you can always be bad psychologyst).
Clinical psychologists always manipulate their patients, not just on bad days.
The 'truth' of math is only that of tautology. One could romanticise it by imagining mathematicians exploring chaotic worlds of their own creation without a map (yes, they're artists!). The reality is that few have the patience to pursue pure mathematics (you would know if you were such a person as you would be solving problems that take days or weeks to solve in your spare time). If you're a bad mathematician, then you won't get results. Ever.
Applied mathematics on the other hand has crossovers with engineering or science (including computer science). How much do you know about computer science or engineering? Programming and engineering is very much applying pre-established algorithms over and over again. There is both attention to detail and creativity required, but this usually has to do with the compromises involved, rather than, say, elegance of the problem. These fields can sometimes seem exciting as an outsider and potentially mundane as an insider (depending on your preferences).
I think it is a big mistake to concentrate on 'safety' or mix of science/math when choosing a career. What you need to consider is what those in the field actually do and whether you can put yourselves in those shoes. In terms of scientific fields, the
papers that are written. In terms of engineering, the procedures that are followed to complete a project. Medicine has a huge range of possible niches in that regard, but you still have to waste a lot of time 'paying your dues' practising on the frontline until you can work towards those niches.
And so it goes for all the
other possible careers.
Next, once you have narrowed down the list, you will need to ask people in those careers lots of questions. From the proportions of time spent on each aspect of their jobs, what frustrates them most about their job, to future career prospects. The only way you will really know what you are getting yourself into is by talking to real people in those fields. And that means that you will need to contact people who aren't on forums like this one. Don't get caught up on career questionnaires or career advisors either, nothing substitutes for talking to real people and putting yourself in their shoes.
If you have a month to decide, then you should be spending much of that time solving this question, rather than deciding prematurely.
, or at least bigger than in medicine where i simply dont like any field. even psychiatry is something that i'd never had anything to do with because i dont believe in psychiatry, meds, etc. 
