My doctors said that my avm is located in c3-c5 level of my spine but then, last october I had my 1stt angiogram everything's normal. What should I do?

Sounds like you may . Not have one but get a second opinion and bring all your studies with you.
Get follow-up. A spinal avm is very rare. There are different ways to look for it. Mri is a good screening tool. But, the angiogram is considered the gold standard. You may consider a follow-up MRI to see if there is any abnormality. You may also have the case reviewed by another neurosurgeon. The quality of the angiogram is also important. You may check with your 2nd opinion that it is good quality.