federal refund mailed

hi, i mailed in my federal and state refunds because i do not remember my 5 digit pin (i am not sure where or how to make a new one or figure out my old one). i filed feb 23rd, and i received my state. my federal has still not been direct deposited to me and i have checked my status and nothing comes up. like nothing is there to show me. im beginning to think i did it wrong but i KNOW i followed all of the steps when it came to mailing it. im not sure what to do but it is May now and everyone around me has received their tax refund. Ive gone to irs.gov and tried to get my status and again, there is nothing to show.