It’s impossible to give a diagnosis over the internet. I can, however, comment on some of the symptoms you have described.
Talking to yourself: it’s not uncommon for people to do. It’s especially common among people who used to do it as children. It seems to bring comfort. You do it in private. If it helps you and there’s no other problem with it, then I don’t see anything wrong with it. If you were doing it in public and it caused a distraction, that would be a problem. If you wrote that you had trouble deciphering the difference between reality and your imagination, that would also be a problem. Because it benefits you and it may not harm you, it seems fine. However, only an in-person evaluation can make that determination.
Mood swings: most people are moody from time to time. Moods can be particularly unstable during PMS or when tired. When you’re tired, it’s natural to be irritable. What is less common are drastic swings in mood. That is not the norm. You seem to go from one extreme to another. The inability to concentrate or even finish a sentence are also not common symptoms of mood swings. They may be indicative of a potential problem and should be evaluated by a mental health professional.
Cutting: cutting behavior is always a worrisome sign. It could be a maladaptive coping mechanism that you have developed over time. Some people who engage in cutting behavior do so because they believe it brings them relief but that relief is temporary and ultimately ineffective. Self-destructive behavior is never a good solution to any problem. You can learn alternative ways to respond to difficult or emotional situations with counseling. The sooner you learn more effective coping strategies, the better you will feel. No one should have to cut themselves in order to feel better.
Not feeling guilt or sympathy: out of context, this has little meaning. I would need much more information about your feelings of guilt or sympathy, or lack thereof, in the context of a situation, to know if this is a problem.
Having trouble dealing with other people’s emotions: again, this is difficult to comment on when there is no context. Most people struggle to deal with other people’s emotions. In fact, many people struggle to deal with their own emotions. More information would be needed to know if this is a problem.
Manipulative: this is a judgment call. You may or may not be acting in manipulative ways but without more information, that is difficult to know.
Arguably, no one is “100% normal.” Normal is relative. Some of the symptoms you have described (namely extreme mood swings and cutting behavior) warrant an assessment from a mental health professional. Thankfully, treatments exist for these symptoms.
You might also consult a psychiatrist for medication. Medication can be quite effective for mood swings. It’s also important to address your cutting behavior. With counseling, you can learn better ways of managing strong emotions. Cognitive behavioral therapy is particularly good for these issues.
Thank you for your question. Good luck and please take care.
Dr. Kristina Randle