A negative test on day 36 doesn't rule out pregnancy yet. Your cycles have been running 41 to 42 days for three months now, longer than your usual cycle length of 33 days. That means ovulation may be happening later than before, which pushes your expected period out further too.
Next Steps
Repeat a urine test in 4 to 5 days if your period still hasn't come, or get a blood beta-hCG test now for a quicker answer. Cycles stretching out like this over three months is also worth a hormone panel and pelvic ultrasound to check the cause.
Health Tips
Please see a gynaecologist if this irregular pattern continues, so the cause can be identified early.