I am being diposed regarding a lawsuit against a company I no longer work for . Do I need to hire my own attorney?

The attorney for my old company somewhat pressured me to have them be there for the deposition. However, I have knowledge that there were some things that were done within my company that may come to light with my information. The company is very large and it is going to the Supreme Court for a decision. The company is currently on a watch list and can not afford to be found doing anymore illegal activities. I was deposed a year ago while still employed. THe company thought the lawsuit was over and then fired me. The last deposition the bosses were on the phone along with attorneys. I feel pressured and know that this company has done many things that may alter how they are viewed in a court of law.