Urine odor is related to the volume and concentration of a variety of chemicals excreted by the kidney. Normally, diluted urine doesn't have much odor. If you're dehydrated and your urine becomes highly concentrated, it can have a strong ammonia smell. Many foods and medications such as asparagus or certain vitamins also can affect the odor of urine.
Most changes in urine odor are temporary and don't indicate serious illness. But sometimes an unusual urine odor can be associated with an underlying medical condition, such as a urinary tract infection. If you're concerned about the odor of your urine, talk to your doctor.
In your case, the use of the self tanner is coincidental. Increase the amount of water you drink today and the odor will dissipate. It is important to drink enough water everyday to avoid dehydration. Drinks like soda and iced tea contain caffeine and can also cause a person to become more dehydrated.
Let me know if you have questions.