As long as your questions are not answered in the above proposed answers, I have to post mine. Here is my own analysis for such a colloquial expression that is used is more common in lower Egypt, while in my region in upper Egypt ما بقتش is more common.

First: the MSA equivalent
ما عدتُ I am no more


first person negated past tense but it indicates the present as well. It is like the English present simple or present perfect

Second: sheen indication
In the Colloquial Egyptian Arabic, ش is added at the end of words to indicate negation, e.g., ما أكلتش، ما فيش I did not eat, there is nothing
ش is basically contraction of ،شيئًا أو شيء anything
Hence it is ما أكلت شيئًا I did not eat anything, then, it is used to indicate negation even if the the word "anything" is not there as in the word in question. The same applies to "ما بقتش" because if we are going to translate it in light of the rule of adding /sheen/ to words, the literal meaning will be "I am no more anything!!"

So, ش is added to the verb عدت to be in harmony with other verbs that have such a contraction as a suffix to indicate negation.
Then it becomes ما عدتش

Third: ما عُتّش

letters of /dal/ and /taa/ are from one place of articulation, so they are assimilated and pronounced as two taas that some people pronounce it as
ما عُتّش

Fourth: adding extra /noon/

some people tend to replace the shdda (stress or emphasis on letters) and double letters with /noon/ letter, e.g., some people pronounce ممتاز as منتاز

Accordingly, it becomes ما عنتش

Fifth: Yes, the tense is past


Best,
Saleh