Thanks for your query.Based on the facts that you have posted it appears that you have what is called as Fissure in ano
which is a small ulcer over anal mucosa that gives you burning pain after passing faeces.
Please take stool softener
like Softovac granules regularly everyday evening
Modify your diet and take leafy vegetables ,spouted cereals and fruits .
Drink more water all these things help in softening the stools .
You can use Lignocaine Jelly to sooth out the anal canal