um, my girl started tantrums around 1 yr old and they were horrific too. I have been told that at that age, through age 4 is normal.
Just try to ignore it. If you give her any attention -- good or bad for them, she will keep doing it.
It *****. It will pass though.
I think she may also be undergoing change in her body that would make her feel uncomfortable and would resolve to such behavior. You may want to see your doctor and ask their opinion about it. If you are having a close relationship with your daughter she might tell you why she is doing these things. Try to ask her when she is on a good mood.
The only thing I can suggest is to allow her to take her temper tantrums until she's finished, then speak to her and let her know you don't like her temper tantrums. I know that she may not understand completely, but if you ignore the temper tantrums, she'll hopefully get the understanding that she isn't going to be picked up when she cries. Let her get as much energy out as possible. Let her play as much as possible. Try to redirect her if she gets frustrated with one activity, get her involved in another activity. If that doesn't work, try the nap thing. Naps are always good for both the child and the parent! It is very hard raising children especially when they don't have the ability to tell us what they need verbally. I have a 10yr old, 7.5 yr old, & a 17 month old. Don't ever be afraid to ask for help from friends and family. If someone is willing to take your baby for even an hour for a day, take it! You can get so much done in an hour even if it is only soaking in the tub or getting your hair cut or shopping or housework. It will give you the break you need, and keep you sane. Good luck.