Hi,
I am an MDS in Oral Pathology - tongue lesions are my speciality, so I understand your worry about cancer.
The area you have circled on the tip of tongue in the photo is inflamed / prominent fungiform papilla - commonly called Transient Lingual Papillitis / Lie bumps.
This is completely benign and NOT cancer. It is very common.
Cancer of tongue typically presents as a long-standing (>3 weeks) non-healing ulcer with pain, bleeding, hard margins, difficulty in moving tongue - which is not seen in your case or photo.
Why it happens:
1. Local trauma - sharp tooth / accidental bite / hot & spicy food
2. Acidity, stress, lack of sleep
3.
Vitamin B12 / Iron deficiency
4. Smoking / tobacco / strong mouthwash
You mentioned it is there since 1 week, no pain, no difficulty eating - this also favours a benign inflammatory cause.
Next Steps
1. Is there any history of smoking / tobacco / pan chewing?
2. Any acidity / recent fever / go change in toothpaste?
3. Is there burning while eating spicy food?
Health Tips
1. Don't panic and avoid constantly touching it with teeth - it increases inflammation.
2. Maintain good tongue hygiene - clean tongue gently with tongue cleaner twice daily.
3. Avoid very hot, spicy, acidic food and smoking for 7 days. Drink plenty of water.
4. Do warm saline rinses 2 times a day.
5. Usually this resolves on its own in 5-7 days.
If it persists beyond 2 weeks, increases in size, becomes an ulcer, bleeds or you develop multiple such bumps, please visit an Oral Medicine / Oral Pathologist in person for a clinical examination.
Hope this helps. You can upload a follow-up photo after 7 days if needed.