yours truly here c:
and i swear to the lord, i've been doing 1:30am allnighters b/c of two 3/4s.

I'm doing two 3/4s and all I can say is that I'm actually surprisingly doing well at allocating adequate time for my 3/4s, whilst ensuring my 1+2s are not neglected. Organisation is the key to everything - it is imperative you devise a list of everything you endeavour to complete in a given day or so, and work accordingly. For instance, (I am not aware if your school gives you study periods), I complete a lot of my homework during the study periods. Upon coming home, I rest from 4-5, and then begin homework. I do some quick revision for my 1+2s and complete any necessary homework until 7. Take a 10 min break. from 7:10 - 9:20 I do any Biology homework and a lot of Biology revision. Take a 10 min break. From 9:30 -11:00, I finish off any Further Maths revision, and go to bed. This is a standard weekday. Of course, if I have an upcoming SAC for one of my 3/4s, my whole day is devoted purely to revision for that. I also devote about three or four hours to studying for any of my 1+2 SACs.
Weekend:The weekend revision for me is purely devoted to Biology and Further. I just do some much revision during these days because its a great way to consolidate the ample information (especially in Biology), as well as assuage my stress/anxiety that I have done insufficient work.
Study for any SACs - all my Biology SACs are on a Monday, and many of my Further Maths SACs on Wednesdays, so you devote the day before the SAC purely for that subject.
Wish you all the best and I hope the tips I've mentioned do assist you!