This is serious. If you do not demonstrate significant improvement, i.e. a 2.5 GPA the following semester, you will be considered for suspension. You need to see an advisor immediately to discuss your situation. College is typically much more work than high school. Be prepared to spend at least two hours on homework for every one hour of class time.
Most students have to work.
Make sure you do not sacrifice your grades for your job at IHOP, or you may get to keep that job for longer than you planned. However, every student has a unique situation, and you can decide how to balance school and work. If you really need to work more than 20 hours a week, consider reducing your credit load. Borrowing money to help pay for your education definitely makes more sense than paying for a class you fail because of work. Be aware of your options.