Yes, ladies are supposed to have a natural smell and taste, but it shouldn't smell overly bad. A fishy smell is not normal, it is often an infection called Bacterial Vaginosis which is caused by an overgrowth of natural bacteria in the vagina, it is somewhat similar to a yeast infection. It is common and treatable but the smell and other symptoms associated are clear indicators that something is off-balance and that a prescription is likely needed.
http://www.medicinenet.com/bacterial_vaginosis/article.htm
To the OP, it seems like you may be a little distracted and not really enjoying yourself possibly because you aren't feeling good about the sexual encounters you are having in their entirety. Maybe you are in a stage in which you are generally disinterested in sex and the new development of not enjoying DATY is a "symptom" of that feeling. Everyone goes through stages like that where you just aren't interested in sex, it's normal. Maybe try to think about the encounters you have been having lately and try to consider if there has been something lacking for you other than the thoughts you've been having that are bothering you.
Both partners have functions of their genitals that maybe aren't the most sexually stimulating but those functions are basic, integral parts to innate attraction, procreation and therefore sex. If you weren't distracted by something else and possibly not enjoying where you are, I bet you would be thinking about how wet and tight that juicy pussy is instead of those other not so nice things. Good Luck!