What is the ruling on entering into a state of ihram from Aisha Mosque for someone from Jeddah, with prior knowledge of the obligation to enter into ihram from Jeddah?

If you are a resident of Jeddah, you must assume ihram for 'Umrah from there, because it is now within the Miqat. If you did not intend 'Umrah until you reached Masjid Aishah, you would have passed the Miqat without ihram, and a sacrifice (hady) would be required of you.

However, if you intended 'Umrah while you were in Jeddah, your ihram would have commenced. Wearing sewn clothes after ihram due to the excuse of not having ihram garments necessitates a fidyah (expiation), which is one of the following options: fasting three days, or feeding six needy persons, or sacrificing a sheep.