I'm graduating with my HBSc very soon and will start my Masters once accepted. I did a double-major biology and psychology with a minor in criminology. I initially enrolled in psychology because like you, I wanted to be a criminal profiler, especially after watching Criminal Minds. In several courses there were people who visibly suffered from anxiety and as much as a detriment, it can be a benefit because not only do you learn the theoretical aspects of it but you can apply first-hand knowledge that many other students don't have and cannot appreciate. You won't be able to take a forensic psychology course right off the bat, you'll need to do first-year and at the very least second-year psychology courses. In my case I bounced around with my programs and eventually landed in neuroscience/neurophysiology (including disorders from brain damage), pharmacology and pathophysiology. I wrote several course research papers and a few combined physiology with psychology (i.e. neuro-imaging scans and neurobiology of psychopaths) and one paper combining neurophysiology with criminology.

Obviously I'm biased but keep an open mind because when people first enter psychology, and I was guilty of this as well, I was unaware of the various fields of psychology so don't be afraid to dabble in other areas. Neuroscience has a tremendous contribution to psychology and profiling, although I've found that it's a hit-or-miss, some people love it and understand it whereas others hate it and are confused. Since you have some biology knowledge given your background in nursing, so give it a try and if worst comes to worst, drop the course.

I would recommend you take several courses in sociology and law or sociology of law as it will greatly help you with criminology. If you passionate though, which you seem to be, you'll do fine. In psychology courses, students wouldn't look at you as though you escaped from a freak show, rather they'll be interested because most psychology students are quite interested in abnormal psychology. If you're still concerned, speak to the professor in their office because every single psychology professor I know is very sympathetic, even if they appear as ball-busters.