Advice for dealing w/ pressure

[worldno1]

Hi guys!
I'm a Year 11 student at one of the top NSW selective schools - currently studying an accelerated subject with a relatively small cohort (<1500 in NSW), with my HSC exams happening this year.
I've been placing a lot of pressure on myself to state-rank in this subject; after a successful prelim year, I feel that everyone is expecting it from me (that includes peers, family etc.). However, because I'm aiming to rank first internally, I find myself comparing myself to my peers more and more - such as if they've beaten me by half a mark, one mark etc... This has placed so much stress and pressure on me; can't even begin to describe the number of times I've come home in tears, after I think that I've 'messed up' an exam. To be honest, I hate this mentality but can't seem to stop these thoughts.

How do I get at least reduce these expectations in the lead-up to trials? I feel like my self-inflicted pressure to do well is doing more harm than good. :/