It's safer than what people say. I passed twice and the check points are quiet exaggerating the situation. Maybe there looking for contraband, weapons, combatants, criminals, etc at those check points. Otherwise your safe to go,no big issue.
Try the procedure I told you. Lucky enough you still have until 30th on your visa. Indian embassy in Bangkok they can replace your passport within 5 working days and that is only if immigration office fails to help out,which won't happen.
Visit airline desk at the airport soon as possible,and see what they say. If there not willing then proceed to the immigration office within the airport. There helpful and they will surely help you out
Go to the airport earlier and visit immigration office. They will issue a pass for you. The most important page is the bio data page,if it's visible no issues. As for the stamps, immigration officers can help you out as it's all electronically documented. Again visit the airport today if possible for your safety as the process takes time.