It definitely sounds like some sort of psychosis. For it to be schizoaffective disorder, you need to have a combination of bipolar disorder and schizophrenia. People with bipolar disorder can be psychotic (have hallucinations and delusions) during episodes of depression, mania, or both. However, once their mood returns to normal, their psychosis remits. In schizoaffective disorder, a person will have mood episodes of depression and mania, but once returning to a normal mood, the psychotic symptoms will remain. This is why it is a mixture of both schizophrenia and bipolar disorder.
Have you read descriptions of mania/depression? Do you fit those criteria during your three months of hallucinations/delusions? Paranoia, especially with persecutory themes of spying/cameras and aliens, usually are indicative of schizophrenia-type psychosis or non-mood episode schizoaffective psychosis. In psychotic depression, psychotic symptoms tend to be themed towards punishment, guilt, and death. Psychotic mania often is filled with grandiose delusions. This is called mood-congruent hallucinations/delusions, since the psychotic symptoms match the mood episode symptoms.
Since you know now that your hallucinations/delusions aren't real, the psychologists/psychiatrists will delve into that, too. Based on your description, though, it sounds like classic paranoia psychosis, rather than obsessions in Obsessive-Compulsive Disorder. (I have OCD, so I can explain the difference between psychotic thoughts and obsessions more, if you'd like.) They also likely will check to see if these symptoms happened naturally or as a side effect of substance/medication use. You probably will be given some psychiatric evaluation. The SCID is a very common one used, and you will be asked diagnostic questions for various disorders to tease everything out and create a general diagnostic impression.
Another clue that you are indeed suffering from a psychotic disorder is your age. You said the hallucinating period happened while you were at university. Psychotic disorders almost always begin in late adolescence/early adulthood. It is still uncertain why this is, but it's believed to be associated with how the prefrontal cortex (PFC) doesn't fully "turn on" and gain some of its advanced cognitive abilities until this time in development. Both the dorsolateral prefrontal cortex (DLPFC) and ventromedial prefrontal cortex (VMPFC) have been heavily implicated in causing psychotic symptoms. I hope your evaluation goes well, and please let me know if you have any more questions.