Many people have reported a similar experience after engaging in drug use and subsequently being unable to return to their “normal” emotional state. Individuals can be negatively affected by drug use, even after just one use. That is the primary reason why the use of illicit substances is dangerous.
What may be happening to you is that this incident could have triggered the beginning stages of an anxiety disorder. Individuals with obsessive-compulsive disorder (OCD), for instance, can become intensely focused on their thoughts and in some cases, may continually worry that something is wrong. That is the essential nature of OCD. Because of the difficulty you have expressed with regard to your negative thoughts, I would suggest seeing a mental health professional.
Seeing a mental health professional is advantageous for several reasons, including being able to have an objective evaluation about whether you are developing an anxiety disorder. Another reason that it would be in your best interest to see a mental health professional is because he or she could teach you how to properly handle your negative thoughts. It is important to gain the skills necessary for managing your symptoms to help prevent the development of an anxiety disorder. Click the find help tab at the top of this page to locate a mental health professional in your community. Please take care.