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Hi  Pali Study Group.

I'm a new student of Pali, working independently. Was hoping to get
clarification of a couple of terms. Am working on the
Sakuṇagghisuttaṃ, which is Sutta 1 in the Buddhavacana text
by Wallis. In the third sentence, there are the terms:

"myāyaṃ" -- like the relative pronoun yāyaṃ ? But
why the initial "m" ? Possibly related to the preceding word "na" ?

"yuddhāyā'ti" -- like the dative singular of yuddha, which
should be yuddhāya ? But then why is the final "a" long, instead of
short ? Is the "a" lengthened because of the combination with the
following "iti" ?

I apologize if the answers are obvious, I am a beginner. Thanks for any
help. SCB