i think im a schizophrenic

hey all my name is jj and im 18
just recently ive been really paranoid about a lot of things and it really worries me now to where i cant sleep comfortable. just last night around 5 am i had a bad panic attack because i kept thinking about schizophrenia and imaging weird random thoughts that dont make sense. I am not sure if i developed something that causing me to be extremely paranoid from smoking weed. ive smoked weed really heavy since the 9th grade and i stopped just 4 months ago (i am a senior now) i only stopped be cause my sister told me i was going to get schizophrenia and also because i felt like i was being weird from smoking. im am really scared to lose my mind and not be the same again. whats even worse is that schizophrenia runs in my family and my grandpa has it currently. i cant even keep my mind busy without thinking about it constantly. i dont start therapy till February 8th and i need help asap i dont want my paranoia to get worse. if anyone can talk me out of it or help me id be really grateful.