Oh, I understand how these thoughts can drive you crazy! But scientifically, pregnancy absolutely cannot happen without intercourse. I used to search Google for hours over such doubts, but don't worry, it is physically impossible.
Have faith and keep your mind peaceful, dear. It is physically impossible to get pregnant without intercourse. If you are feeling anxious, just take a deep breath and pray, everything will be fine.
Let me share a practical fact: pregnancy requires sperm meeting the egg, which doesn't happen without intercourse or medical procedures. If you are stressed about late periods, it's very common, just do a simple home test to be completely sure.
Naturally speaking, it is not possible to get pregnant without intercourse or medical treatments like IUI. My mother always says to keep our mind free of such doubts. If you are missing periods, it could be due to stress or hormones, so please consult a good doctor.
No dear, pregnancy cannot happen without intercourse. Don't worry at all. If your periods are late, just relax and wait for a few days, sometimes stress delays it.