Forgetfulness. A very low self esteem.

Hi, I am a 30 years old female, working as an IT Professional.Its been a while I am worried  of this condition of my forgetfulness. Used to be a bright student back then and had a very sharp memory but 6 years back this issue started. Later I got diagnosed with thyroid. It was hypothyroidism with a TSH value 100+. With medication thyroid gets better and now in control with TSH value less than 5. But been few months again this forgetfulness is getting worse and I am not sure what can be the reason. Sometimes I am thinking is it a neuro problem or do I need a psychiatric if I am into depression. I am not sure what to do but it's affecting a lot my professional and personal life as I am not able to remember anything properly.I started self doubting myself which leads to a very low self esteem.