I'm not passionate about anything anymore and don't know what to do with myself.
I feel your downheartedness, but why do you feel you're not passionate about anything anymore?
I'm not sure, I thought I am into philosophy but I am not sure anymore.
It's okay to lose passion about a particular thing like philosophy, and you may end up having a different passion in the future. But if you think you can't be passionate anymore with anything, I suggest you get help so that you can resolve your problem and have a more meaningful career with something you care about deeply.
Philosophy is not passion involving. It's boring.
Then that is okay. If you are unsure of philosophy then you can still change your major and look at other things you can be interested in. I hope you find something you like and are interested to make a career of someday, good luck!