Hello! First of all, don't stress. Seriously, it will make things worse for you if you are constantly stressing.
To answer your first question: It was difficult, I won't lie to you. Seeing your friends do well and disappointing your teachers is hard. What is comforting for you is the fact that it is only November, you have been there two months. It is natural to under perform at this stage and then bring it up as the year progresses. However, don't rest on that as that progress takes work. The way I dealt with it was the fact that I knew I could do better, so I pushed myself. I saw those grades and hated them. I researched every revision channel on youtube, looked at grow your grades to find out HOW I could do well. If you want to improve, and i mean REALLY want to, you will push yourself to do so
For your question about predictions for university: No, it really didn't effect them. My teachers knew what I was capable of and the fact that you are at a point so early in the year is important because if you turn it around by July they will see the progress you have made and make your predictions off that
A good question, How did you do it? Well, I first of all gave myself a good shake to sort myself out. I then put all of my effort into every piece of work I did. If it wasnt what I wanted I would do it again and again until I got the grade I wanted. I tracked my progress to show that I was actually going up, because it isn't instant and I also talked to my teachers and older students. The last part is rather essential as your teachers know a lot more than they can tell you in a lesson, so make use of it. Older students can let you in on tips and tricks and help you get ahead of the work if you have the same teacher as they usually use the same structure each year.
My least favourite question, how many hours did you study? If I'm honest, I don't know. I didn't meticulously count (although I tried at one stage). It is more the QUALITY of the studying than the quantity. I could study for 10 hours and I could achieve the exact same amount of learning as if you did 5 hours. It is so subjective and really depends on your pace. As long as you get everything you need to done, the hours don't matter
You don't have to sacrifice everything. I have maintained two jobs and a social life throughout this.. although i did lose out on sleep xD If you have the dedication and commitment you will do it. Every minute adds up. You check your phone for 5 minutes every hour you are awake? There is an extra hour of studying if you just do it before you go to bed. Oh that 3rd episode of your favourite TV Show is about to play after you just watched the other 2? Why not complete half a past paper and save the 3rd episode for later on? Its the little changes that really count.
Please, don't worry about asking too many questions, thats how everyone learns anything... by asking questions! Please don't be too downhearted about your results, because if you truly feel that you have underperformed and want to put it right, you will!