A First, discuss your concerns with your daughter's teacher.
When a child hasn't begun to read, memorising lists of words by rote is not helpful. Children are usually able to read before they can spell, so care needs to be taken that she's ready for spelling.
If your daughter does continue to bring spellings home you could try making them into games. Write the words on small pieces of card and play lotto, snap and pairs with them.
Plastic letters and magnetic word tiles can be bought cheaply from shops such as the Early Learning Centre. You can then play at word building with the letters - make family names, familiar words and words with the same pattern - for example, sit, fit and kit. You can also play sorting games with the tiles - find the words beginning or ending with a certain letter or group of letters (such as '-ing').
Also, find opportunities for writing together. Try lists, cards, letters and stories, and use the computer if you have one.
These activities should be fun - try not to pass your anxiety to your daughter, however difficult that is.