only you can say whether this was weird or not. all we can do is read your posts and tell you if this would be weird if it happened to ourselves. no it would not be weird for this to happen in my life. situations like this usually have more details then what you have posted. example what was happening in my own life at the time, was I dating someone and my parent discovered it, did I discover my parent out with someone else, what happened with the dad before walking in on 20 year old me to tell me he had been out with another woman not my mother, did my mother maybe threaten to tell the family so was dad telling me first, ....

my point is on the internet all we get are snippets of a persons life not all the supporting details that actually witnessing the situation would give us to decide whether something is weird for another person or not.

which is why I tend to err on caution and dont tell others online whether they have this or that or whether something in their own lives is wrong or not, weird or not, only you know all the info of what the complete situation was, so only you can decide whether this was wierd or not for you.