Losing something sentimental is very hard to replace. Did you
ask her what memories does the phone contain? Is it about you and
her? If it is, you can try to make it up by showing her your phone,
if you kept pictures of her and you together.
Let her have some time to cool down. Contact her again a few days
later. Ask her out for lunch. Ask if she's still angry. Do
something to cool her down, like bring her to play or
something.
About education, you can upgrade yourself anytime. Don't be
hindered by the difference.
You can try searching all the shops, but doubt you will get it
back. If there are sensitive things inside, make a police report.
Otherwise, take it as a lesson learnt.
