By far the most likely possibility here is that you are simply not drinking enough water. When the body does not have enough water, the urine will taken on a much deeper yellow color and it will have a stronger ammonia odor. This is actually normal, and it is the kidney's natural response to preserve the body's water content. Generally, this will respond to increasing your intake of fluids, but you have to keep up the increased water intake long term, at least 8 glasses of water a day. You also have to avoid dehydrating beverages, such as coffee, tea, soda, and alcohol, as these defeat the purpose of drinking more water.
If this does not clear up the problem, then it is probably worth going to see your primary care doctor
, especially if you have other symptoms such as burning with urination or abdominal or pelvic pain. These could be symptoms of a urinary tract infection
. Also there are other conditions that could give you these urine symptoms, depending on whether you are a man or a woman (can't tell from the question). Your doctor will be able to take a urine sample and help you figure out what is going on.