FLUPHENAZINE??
Well, that's a first! A really old-school antipsychotic, which is quite weak and has multiple problematic side-effects, which is why it is no longer in use in multiple countries around the world - there's a crap-load of better antipsychotics to use.
With that said, why were you given Fluphenazine in an injection? The only use in most jurisdictions is for the treatment of schizophrenia, when there is an issue with compliance - did you refuse to take your medications?
As a side-note, I wouldn't worry about the Decanoate portion - Decanoic Acid is a naturally occurring compound in mothers-milk from multiple mammals, as well as a fatty acid - it can also be found in VERY HIGH amounts in Coconuts - coconut oil contains up to TEN PERCENT of this stuff! Yet it's not considered a hazard - in fact, many consider coconut oil a much more healthy alternative to other cooking-fats, and have been used traditionally for MILLENNIA.
Apparently our own bodies ALSO produce this compound, when entering ketosis - people on ketogenic diets have naturally occuring HIGH levels of this acid in their blood, and this is the reason why Ketogenic Diet works quite well for EPILEPSY - Decanoid Acid is a highly potent anticonvulsant.
Many, many compounds have been used for the manufacture, or as semi-potent pesticide's in the past - Citric Acid, the stuff from lemons, was once a semi-reliable pesticide, for certains pests. Citric Acid is in no way lethal to mammals, as I'm sure you're aware...
Right, back to your issues - I suggest you talk to your Dr's about problems with a lack of motivation and anxiety, and a dulling of cognitive processes.
The difficulty to motivate yourself may be connected to your antipsychotics - the best bet here, is to replace your antipsychotics with something better and add substances which improve negative symptoms, they are as follows:
Aripipazol
Brexpiprazol
Cariprazine
(the above are THIRD-generation antipsychotics, wherein Brexpiprazol has such an unusual mode of effect that it's considered the first in a new class of substances: SDAM's - Serotonin Dopamine Activity Modulator - they have a much better side-effects profile than crap like Fluphenazine - Brexpiprazole for instance, is the first antipsychotic to be officially allowed for the treatment of depression - that's HUGE!)
Ondansetron (anti-nausea pill - recently found to improve cognition in schizophrenics)
Vortioxetine (antidepressant, works partially like ondansetron, a 5ht3-antagonist)
Reboxetine (antidepressant, increases activity of norepinephrine, unlike typical antidepressants)
You may also have to come to a realization as well:
Schizophrenic psychosis causes permanent brain-changes and cognitive problems.
Many Schizophrenics are extremely, extremely resistant to this idea, that some of their cognitive issues are not as a result of their medications, but by their disease - that newer, and older yet forgotten, research have come to the conclusion that Schizophrenia is a form of DEMENTIA - a progressive pervasive disease which kills brain-cells - but still, it's the truth.
Psychosis is a feature of another form of dementia as well: Alzheimers. It's also a feature of Parkinson's disease - another neuro-degenerative disease.
Schizophrenia is, unless you have the NON-classic forms, i.e Simple Schizophrenia, Schizoidal Personality Disorder or Schizotypal Personality Disorder, a progressive disease - one of the symptoms that get worse, is a lessening of cognitive abilities - i.e Negative Symptoms. (admittedly, some schizophrenics whom have the paranoid variation do not experience cognitive decline to the same extent - instead it's the hallucinations that get worse with time)
What you're experiencing could to an extent be a result of damage to your brain from Psychosis - did you experience such an event? If so, you have to take this possibility into account.
Those symptoms can be conquered as well though, but it will take time and effort, with dedication from you and your psychiatrist. Raise the issue with her, and press her for further treatment of the issues you are describing - any of the compounds I listed could help with your issues.
Vortioxetine and Reboxetine can be dangerous without concurrent use of an antipsychotic though, it should be noted.