If you are stressed a lot with no known cause, then it could be that a trip to the doctos is in order. I had this for nearly eight years before I was diagnosed with Severe Anxiety Disorder and needed treatment.
In the short term teas like Chamolime can help, but they are no solution to a more long term issue.
As a health major, I can tell you that random bouts of stress is extremely normal for people to have at times. Usually, it can be relieved by getting more sleep, decreasing the amount of caffeine you drink, and the possibility of doing Yoga or some other form of calming exercise. However, if this stress starts to interfere with your daily life, then a trip to the doctor's is needed.
I mean, if a home remedy does work for you, then that's great! Usually a nice cup of herbal tea does the trick for me. But if you physically cannot handle a basic day of life because you are too stressed out and nothing is working, then I highly recommend you talk to your doctor or a psychologist to figure out why you are stressed out. It really isn't as bad as everyone thinks it is :)