Well in my freshman year I made 4.5 credits and had to go to summer school, then I made up those credits and rn its second semester (10th) and I only have 6.5 credits 
I definitely do not wanna take summer school again and I have 7 classes to take but will I fail???
Btw how many credits I need to be a junior???
That depends on your school. You need to talk with your guidance counselor about this.
How many credits are you supposed to take per year?
Are you signing up for that many credits?
Are you passing your classes?
If not, what is the issue?