You are cursed. Yes, that's right. I'm agreeing with you. I'm not here to tell you that you're wrong, that you're too young to understand, that you haven't experienced enough of the world to say that you're cursed. But you are right to think you're cursed. You just don't understand what's behind it, what's causing it. Here's what's going on:
Other people are grieving just like you are, and now they don't have as much energy to devote to you as they normally would. They aren't in good moods, and they just don't have it in them to be there for you the way that you need them to be. When you combine that with the fact that you need them more now than ever, you have a problem. So when you notice that everything isn't the same, that people aren't treating you the same, that nothing is quite as fun as it used to be, you would be right. Call it a curse or whatever you want to call it, but I assure you that it is happening, you're not just imagining it.
You are not a functional person when bad things happen, and no one is giving you the break that you need. As a result, everything will fall apart. Of course you're not going to be able to handle all your schoolwork (which there was already too much of) while this is happening. Of course you're not going to remember to bring your books home the night before an exam. That's too much to handle. Call it a curse if you want to, but it's really a matter of not being able to take all the time you need and having people place unrealistic expectations on you, such as that you will get all your work done and get good grades.
Your immune system is suffering from all of the stress you are under from being expected to function, which is why you get sick all the time now. Call it a curse.
There are some times when things are just more important than they are at other times. Like if you hit a traffic jam while you're on the way to the hospital and you're about to go into labor, that's obviously a bigger problem than if you ran into the same traffic jam on your way to meet your friend for coffee. Even similar situations can have factors that make something more or less of a big deal - if you have an understanding boss, hitting a traffic jam on your way to work will be less of a problem than if you have a boss who is going to yell at you for being one minute late. There are situations in which the traffic jam would truly be a curse and screw you over, and other times when it just wouldn't matter as much. Right now, you are in a state where everything is more important than ever, and when things go wrong, it is a mega-crisis because it was just way more important for those things to go right this time. It's not always that bad things are literally happening more often, it's that they are having more of an impact because everything is more important than ever. Call it a curse.
You are cursed. I will never tell you that you weren't. It's just a different kind of curse than you were thinking.