Swipe Back gesture

So guys my iphone 8 plus fell down 2 days ago. And i asked if there was any problem with its hardware. They said if its fine after 24 hours then there is no any problem. Thenthe phone was perfectly alright. Today evening i was using whatsapp. And when j wanted to leave the conversation i swiped to right. Usually it will leave just after i swipe. Today it took like 1 or 2 second to leave after i swipe. Then the keyboard typing was also abit unusual than before. Then i restarted my phone. After that it was perfectly alright. Its is fine now also. But im really scared that if my hardware wouldve spoilt. I spent all my money in this phone . And idk what else i could do. Can anyone help me about whats wrong with my phone. I just bought my phone on january 12th. (Phone is working fine now)