Hi
Welcome to the MedHelp forum!
Slow thinking can be due to depression, schizophrenia, anxiety disorder, and migraine. Please get this assessed by a psychologist and a neurologist. It can also be chronic fatigue syndrome, Vit B12 deficiency or severe anemia. Hence get this assessed, especially anemia, since you also have palpitations. It is difficult to comment beyond this at this stage.
Hope this helps. Please let me know if there is any thing else and do keep me posted. Take care!
Sounds like my Fibro fog. Do you have pain? Have you had your eyes checked, if not get eye test ASAP. If you have pain look up CFS and Fibromyalgia
In addition, i have great difficulty recalling information.