2 mo

Am I overthinking?

Ok so I met my boyfriend when I was 19 and he was 20 and before we became official he slept with someone else. However we then decided to move on and become official, but he did Snapchat a girl who he met on a course but I did ask her and she said it wasn’t ever inappropriate or anything they had a general conversations etc. but he was on a night out and one of his friends kissed him on the lips and he said he walked away straight afterwards but he said he was dancing with her because they was friends etc and I spoke to his friend and she apologised and said it was nothing like that at all and that she was sorry. However this was like all before 6 months in and I’ve now been with him almost 5.5 years. But I keep worrying was all of this cheating? Or am I overthinking. Can I even over think this? His never given me a reason to doubt him other than these few bumps in the road?
Am I overthinking?
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