As far as I am aware, you MUST take the AP TEST in order to get credit for college.
BUT, many colleges don’t give credit for AP test scores.
Many colleges require scores of 4 or 5 in order to give credit.
Many colleges might only give you placement into the next level of the course, and that might only be for a score of 4 or 5.
Colleges make their own rules about this.
I suggest you see if ASU accepts CLEP credits, and take those tests. They may only take certain CLEP scores for certain classes.
It’s really unfortunate that you didn’t understand that you would only get AP credit by having a score. BUT, most colleges will only give credit for scores of 3, 4, or 5. You might not have received as much credit as you thought you would, even if you had taken the tests.
It’s very surprising that your teachers never informed you of upcoming AP exams. What’s done is done. Take CLEP if possible, that will help speed things up.
Edit: Colleges must have an actual score on an AP test because the tests are standardized. So if Teacher A does a great job teaching the subject, it should be evident with the students’ scores. Maybe Teacher B teaches the same subject, but all her students get 1 or 2. Clearly that teacher didn’t teach so well, but perhaps she gave all her students top grades. Having a score ensures that the student knows the subject, or not.