help me!!

<p>Hi- I posted this in the <code>college admissions/search</code> forum, but I would also like some opinions from parents! Thanks in advance! : </p>

<p>I have a question, so I would appreciate if anyone could give me some opinions. I am in a really screwed up situation. I<code>ll try to explain it as clearly as possible.
After finishing grade 9 in Japan last year, I moved to a different country, and I am currently attending an American international school. Because of the different school system, my school put me in a grade according to my age(which was grade 10 at the time). However, because of the different school systems, I only did the last 2 months of 10th grade, and entered grade 11 immdeiately afterwards. This was a big mistake(it</code>s my school<code>s fault), as now I do not have enough credits to graduate, due to skipping almost a whole grade. I was also unable to do the full IB diploma (my school offers it), because it did not fit in my schedule and my stupid GC thought my English was not good enough, because I came right out of a Japanese school.
Therefore, I will be transferring to a different school next year. I can not repeat grade 11, so I will be doing a grade 13 to fulfill my IB diploma requirements. Basically, since I skipped a grade, I am now doing an extra year to recieve the necessary credits.I am really worried about</code>doing an extra year of HS<code>..how much will this hurt me in admissions? (provided that my new GC explains this of course)
I also have another question( sorry this is long). My stupid GC messed up (again) during the school year, and told me my schedule was not challenging enough. So she urged me to change into HL math and physics in November. I took her advice and changed into those classes, which was a HUGE mistake. I managed a B in HL math for the whole year, but I recieved a C+ in physics the first semester ( btw, I changed into those classes a month before the final exams..) I worked hard and got a B+ in physics the second semester.
My physics teacher wrote a letter explaining how I changed into those classes right before exams,and how I improved throughout the year.
I don</code>t want to be whiny, but how much does that C+ affect my admissions( I am looking at competitive schools like the Ivy league and other schools of that caliber.. ) I know it<code>s a crapshoot for anybody, but I just want to know how much the C+ hurts my chances. My other grades are good (A</code>s with 2 B`s) How much will schools consider my situation?
1. coming right out of a Japanese school
2. skipping a grade
3. starting a class a month before finals.
Also, how would I go about explaining this in my applications?
Sorry this is long, thanks in advance to everyone who replied!</p>