Can Zoloft and Concerta be stopped in depression patient without side effects?

Hello doctor,

For the past three years, I have been taking 100 mg of Zoloft and for the past five years, I have been taking 36 mg of Concerta. While taking them, my mood was pretty consistent with only a few times of feeling slightly depressed. But while I took them, I still was overthinking and had stress that consumed my thoughts. But, even when my mood was consistent, I still felt kind of boring. It could be from outside factors like school but I still have excessive thoughts about things outside of school. After taking the medicines for so long and having switched from different medicine before and trying different doses, I thought maybe it is time to cut out the Zoloft altogether. So I went to 50 mg, then down to not taking it at all about a week and a half ago. For the first 10 days I felt pretty much the same but for the past three to four days, I have been very irritable and today especially feel completely numb. Also, today for the first time since stopping Zoloft, I felt the stress and overthinking that I usually felt while taking Zoloft. I have been trying to find the right medicine and amount of medicine for about a total of six years to feel my best. I am not sure if I am just overthinking. Stopping it makes me think that I will be more depressed which makes me actually believe and feel that it is just lack of sleep mixed with female hormones. I really need to find the underlying issue of my feelings and figure out what is best for me. Ideally, I would like to feel my best without medication but the Concerta works well for me. I am not sure if the Concerta plays any role in my mood and stress. I really need guidance. I had Lexapro in the past for the same issue.