Strange chemical smell and taste

Hello everybody,
I have been experiencing the appearance of a strange, chemical smell and taste out of nowhere a few times now.
The first two times i thought it was related to eating a lot. (It was after christmas on my way back from my grandparents, 2nd time was visiting my parents)

But now it appeared again out of no where.

The smell can be described as somehow soapy, reminding me of washing detergent. It also affects the taste, and makes everything taste chemical and disgusting.
It usually lasts the day, or at least a few hours.

At first I got the feeling, that it might be related to my diet, but I am not sure and have no clue what could cause something like this

Here is some general information about my person to help you find out my problem:

Gender: Male
Age: 19
Height: 180 cm (5'11)
Weight: 75 kg (165lbs)
Bodyfat: 10-12%
Fitness: fit (dancer)

Recently (2 months before the first appearance of the symptoms) I have had a blood test done. They checked for about everything and found nothing worth mentioning.

Diet:
- a lot of vegetables
- a lot of protein from lean meats (I try to get 100-150g a day)
- also the occasional sweets (nearly every day)

My weight has been fluctuating between 73kg and 76kg for the past few years.

I have been going to the gym 2-3 times a week for the past 3 years and try to eat healthy.


Any ideas?