First of all, you need to rule out pregnancy
by doing one blood test
for beta-HCG at the earliest. Early pregnancy test may give negative result.
Other reasons for late period with irregular spotting are hormonal imbalance , stress/ anxiety/ mental upset, irregular diet pattern, wt change, thyroid disorder
Consult with your gynecologist for relevant examination & investigation like USG pelvis, complete hormone profile etc
Avoid stress by regular deep breathing, take healthy diet with iron supplements
, keep bowel habit regular, maintain personal hygiene and take proper sleep.
Be well & take care.