According to you it's only 2 weeks, means less than a month, that you are feeling stressed. This doesn't seem to worry much, unless it persists for few months continuously. Little bit of stress is in the environment too nowadays. Can talk to your trustworthy friend, if you feel comfortable, or talk to a counsellor.
Next Steps
If this mood continues for a longer period then go to a psychological counsellor.
Health Tips
Please don't take medication on your own, unless advised by a professional doctor.