My attorney did not do any investigation on my behalf. sh did interview witnesses, cops or looked at the video

No way to tell. Much of this depends on the nature of the charges, the evidence against you, how you got convicted and what you spent on legal represention. If you spent OJ level money on the dream team, you  are right to expect that level of defense. If you found the cheapest lawyer you could afford, whether the lawyer provided adequate defense may be limited by the funds you committed to the defense. Unfortunately, most criminal defendants focus on penny pinching when hiring the lawyer but after they are convicted or don't like the results, have a new found willingness to spend the same money after the fact, that had they invested inthe case earlier, might have made a difference in the result. Unfortunately, this is like wanting re-do your hand in a poker game,  to bet your house AFTER you find you have the winning hand, but folded because you didn't want to risk losing the money when the bet came to you. If you have questions about the deal you made or the penalties imposed, you will need to hire a lawyer at some expense to review the file and what occurred and gofrom there.