Toddler screaming.

I have a 19 months old and she screams and cries almost nonstop. Soothing her doesn't help. Ignoring her doesn't help. Trying to get her to communicate what it is that has her screaming doesn't help. At this point, I'm afraid my neighbors are going to call CPS on me because she screams and cries so much. They probably think shes being abused, which isn't the case at all. We cannot go anywhere without her screaming in the carseat, in the store, or pretty much anywhere. I've taken her to her pediatrician to see if something was wrong with her and he says that she's perfectly fine, nothing health related that would cause it. Just that she likes to scream. Some days my nerves are so shot by the time I get her in bed, that I dread the next day. And don't get me wrong, we have good days, but those are so few and far between.

Has anyone ever experienced this? Do you have any advice on how I can stop this? My mom has told me to spank her, but it makes her screaming and crying worse and doesn't fix it.

I'll take all the help I can get at this point. TIA.