I will be graduating in Dec 2018 but not so sure if this is alright? (pre med)

There is only 2-3% chance for an international to gain admission to a US med school. If you think you still have a chance, you should apply for extension of your visa.
And, you can paying for med school is not the answer, the answer should be “I will have $250K to be put into escrow for tuition and living expense if necessary”