I am sorry to say this, but it really does depend on the level of difficulty, the flexibility of the professor, and your study skills. During my PCT program, I went to school part time (taking courses such as A&P). For me, the PCT course was not demanding at all. Unlike your credit courses, it is a pass/fail class, so no pressure to maintain a GPA.
Also, unless you have a lot of experience as a CNA, it really helps to have those certs for PCT, EKG, Phlebotomy, CPR, BLS, etc. I didn't hear back from a hospital until I got those certs. Maybe it was just me, but it looks like those certs help if you dont have a lot of experience. In the summer in will start orientation to be a PCT in a hospital. I am happy that this position will utilize some of the more technical skills I learned in my PCT program.
Hospitals cannot verify what you learn in school. To cover their backs, they like to see experience or certifications on a resume. This gives them proof of competency to validate their hiring process and avoid a potential lawsuit. All of this depends on the particular hospital. There are some lucky bastards that get can a job as a PCA/PCT right away. Note that the job you would get in a hospital would most likely resemble what a CNA does in a nursing home as opposed to more technical work, such as EKG, Phlebotomy, Foley, etc.
If I were you, I would take A&P next semester. Your PCT program will take months to complete. Test the waters first. Take a less demanding course first, to see how well you are able to manage credit courses and the PCT course. Good luck to you!