Thank you for your enquiry and keen interest in TCM.
After assessing your tongue, you may have a weak digestive system (as seen in the yellow coating towards the end of the tongue).
Food is not entirely broken down and absorbed, which results in fermentation and presenting as bad breath. The tip of your tongue appears red, which signifies heaty in the heart system. You may be undergoing stressful period and tend to sleep late.
This reduces salivary secretion and certain bacteria may flourish in your oral cavity. In conclusion, your body is stressed out, accompanying a weak digestive system.
My preliminary assessment can only be confirmed during a physical confirmation. Herbal prescription is typically used to resolve this.
Hope this helps!
With regards,
Jin Shun