After sex my cum was Brown is that normal?

Not normal . Brown or rusty colored semen is most likely an indication of infection in the semenal vesicles. Usually one is not sick with fever etc but can be. Not contagious and not a STD. See a urologist and take a semen specimen with you if you can.... Clean glass or cup is ok for transport .
Hematospermia. Hematospermia ( blood in the sperm ) is related to many issues: infection, inflammation, aggressive sexual oral oral/anal intercourse. I suggest immediate urological evaluation and semen analysis. I also suggest abstaining from any and all sexual activity for at least one week.