You are responsible for learning the rules and regulations that govern your life at the university. These include your rights and responsibilities, your degree requirements and university graduation requirements.
Where do you find this information? Start with a copy of Texas Tech's Student Handbook, available in the Center for Campus Life, 201 Student Union Building. Pay particular attention to the Rights and Responsibilities of Students in the Academic Community.
Then go to your academic advising office and get a copy of the requirements for your degree, which should include the university graduation requirements. You also should ask your adviser for a handbook that outlines the specific policies governing your degree program. This is especially helpful for graduate students in forming thesis and dissertation committees.
Note: Not all academic departments/schools provide a handbook.
You also will want to read the Texas Tech undergraduate or graduate catalog (whichever applies). In addition to describing each academic program, the section titled "Academic Regulations" tells you policies on such essentials as academic status, refunds, tuition and fees, and dropping courses, grade replacement.
Warning: If trouble arises because you failed to adhere to program requirements, missed deadlines, etc., you are held responsible (unless you can verify that you were given wrong information). You can't use the excuse "no one told me that" to excuse yourself from accountability. It's your responsibility to seek out the information that you need while a student at Texas Tech. It will prevent problems for you.