How hard is the IB in terms of workload, tests and stress?

I just finished my sophomore year in the pre-IB program and it was not too bad except for five or six points in the year. Specifically, I felt really stressed before EXAMS when I had 3 projects due and two big tests in the same week with five exams the week after...ugh. Overall, it wasn't too bad but I'm EXTREMELY nervous about grade 11. I've heard it gets really intense, especially with all the CAS stuff. How bad is IB really? As per the courses I'm doing next year: English A1 HL, Chem HL, French B SL[writing the exam next May], Math SL (NOT studies) [writing the exam next May], TOK and Physics SL. In grade 12 I'm going to do English HL, Chem HL, History HL and Physics SL. I'd really appreciate any feedback and/or advice. I'm really freaked out and will be so grateful if someone could lend me a helping hand. Thanks so much. :)