Weakness In Limbs. MRI Showed Herniated Disc. Is It TIA?

I recently went to the hospital with weakness in right arm and a little in right leg. All tests, CT scan , MRI , chest xray , carotid ultrasound, echo cardiogram, blood work etc. came back negative. I did not have any other symptoms except the weakness. They cannot tell me if it was a TIA but put me on an aspirin regime. I was already taking 81 mg but now have to take 325 mg. The second MRI showed a herniated disc on the left side of my neck but was told that was not the problem. I have to get an EMG but still do not know if it is a TIA. Can you help? Thank you!