After Breakup Depression

So, it's been two weeks since my breakup. I feel a surge of guilt and anger and sadness all over. Clearly, my health wasn't the best after that. I only ate around half a meal a day and do not feel hungry. I have insomnia. But, gladly I'm feeling better now. I feel so hurt but I'm also stressing about my grades because honestly, if my grades were fine. I would not be stressing about the break up. I'm sure someone is going through the similar process of post breakup. Is there any advice for me? Also, I lost around ten pounds within the two weeks basically....does not sound healthy :/