Saeed and Sayid are two different names completely. They have different root letters and so will even differ in meaning. Sayyid mean prince while Saeed means happiness. Adding the feminine taa at the end "ad" will make these names/words feminine- Sayyidah and Saeedah.
Saeed's 'a' is a special throat letter called 'ain' and is written like a number 3 when it is not pre- or sub-joined to any letter.
so first syllable is "sa"
the second syllable is followed by the strong throat letter which i will identify with an apostrophe: 'eed.
Sa - 'eeeeeeed
thats how it is pronounced.
** I am not fluent in Arabic nor is it my first language, by this I do know.