From what you have told me, and to begin by answering directly your final questions, no, there is nothing wrong with you — and, no, there is no reason to avoid suits and ties if you like them.
Allow me to firstly approach your first question: about your confusion. There is really no need to be confused. From what you have told me, it does not seem to me that you have any reason to be at all confused about your ‘true sex’. Rest assured that, if God created you female, the best thing for you is to remain female.
The fact that you do not comply with the average of a certain group does not mean that you cannot be part of it. The average, the stereotype, the most common observation, whatever you call it, is literally just a mere indication of the general behaviour amidst a certain group. You do not have to be part of the average. This applies to everything in your life. For example: the average teenager swears a number of times each day, which does not mean that you (being a teenager) should swear as well, or that you are any less of a teenager if you do not; the average Portuguese person has a tendency to arrive late everywhere, which does not mean that I (being Portuguese) should strive to arrive late as well, or that I cease to be Portuguese by arriving on time; the average human being is not a Christian, which does not mean that we should not be Christians, or that we are no longer humans if we become Christians.
Similarly, you are no less of a woman and no more a man by wearing suits, ties or hats, cutting your hair short, being less talkative, being less emotional or doing any other thing — however uncommon it may be for girls and common for guys. In other words, nothing you ever do will ever mean you have ceased to be a girl and become a guy instead. Do not fear: you really are a beautiful girl, and God has a plan for you which is just as beautiful (or even more). And rest assured that you are definitely not a boy, by any means.
I personally have also had questions over whether my behaviours had been ‘too female’. I have never told anyone because I have never let the issue bother me that much. I quickly realised that this was not a problem. I am a man, and I am sure of it. You should have the same certainty that you really are a woman. If the way you behave is, in any way, slightly different from the way that girls usually behave, that is not bad (unless, of course, you begin to like other girls instead of guys — that would be bad). Again I say it: there is nothing wrong with you; you are a girl.
Now, to your second question — about whether you should dress up more like a woman. The answer is ‘no’. There is no reason that you should change your behaviour so that you should comply with what most girls do. There is no problem if you are different in that aspect. If you like to wear a suit and a tie, then, by all means, do so! If you like your hair cut short, then cut it short! If you do not like to talk a lot and if you are not very emotional, do not worry about that (depending on the circumstances, that could really be an advantage)!
About dressing up, just think about the following. One or two centuries ago, it would have been completely unacceptable to see women wearing trousers. However, in the early/mid 20th century (if I'm not wrong, it was in the 1920s), the trend of women wearing trousers began (with much opposition at the time, of course, because it was too masculine), because it became more and more common for women to go to work, and trousers were a much more practical piece of clothing than skirts and long dresses. Nowadays, it is absolutely common to see girls wearing trousers, and the trend is now mostly unquestioned (except perhaps by a few elderly, closed-minded people)! It is not a problem for women to exhibit manly behaviours.
So, to summarise: do not feel confused, because you really are a woman; and do not bother to select only clothing which your society deems adequate for a girl — instead, dress up in any way you want to!
If you should have any more questions, feel free to post or to leave me a private message!
May the Lord bless you richly!
The Portuguese Baptist