Insecure, Unaware, Disinterested - Please help

After resuming my education after 4-5 years gap, I realize that I cannot no longer focus like before. Since I am doing my PhD now, it is very important for me to be able to focus during lectures, reading papers and discussing with professors and colleagues.

Inability to focus: When reading research papers I cannot comprehend much of it and start using social media sites. During lectures, my mind is usually somewhere else.

Unable to articulate: When professor asks questions, many students seem to be able to perfectly articulate answers. But I am usually unable to do so even though I can solve the problem if given enough time. I cannot access that answer quickly. Same thing happened during one my exams. I do not have a clear picture in my head. However, I was able visualize most of the problems during high school.

Insecurity: I was brilliant during high school and classmates used to call me genius. Some classmates used to tell me that other students were jealous of me because of my brilliance. I used to ignore that and used to help everyone. I genuinely wanted every other student to succeed, and always used to help them understand difficult concepts. But after high school, table turned and I started having feelings of insecurity and jealousy. Honestly, I find some happiness and satisfaction when others don't do very well. I hate being like that, but it is true.

Forgetful: In the middle of the work, I seem to forget what I am doing.

Lack of awareness: My friends seem to be more aware of everything than me from cars, smartphones, cooking, apartment issues.

Lack of interest in anything: Apart from binge watching series, I do not actually like doing anything else. I used to love painting, playing sports, playing guitar when in high school, but I don't do any of that anymore.

I watch motivational videos, however now, even they seem to have lost the effect.

Please help. What should I do?

Just a quick mod note- not to Dx you, but I have moved this to Depression, and left a marker in GAD- anxiety and depression often go hand-in-hand, and this post sounds very like some depression, as well- this allows both forums to see and respond to you....

Honestly, it also sounds to me like you might have some mild depression going on, as well. I know I strongly suspect (and tho we must be careful with self tests, I consistently score high on every one I've taken, for depression and I have many anxiety issues) that I have depression and anxiety, and it's hard to be really super motivated beyond what is necessary to barely survive. You might want to consider talking to a therapist about this- you mention working on your doctorate- is there a campus therapist you could speak with?