I logged into my ex boyfriends email account, is there any way he can find out?

I know, I know this is absolutely terrible, and trust me I feel awful. I had absolutely no right and deserve a slap. Broke up with my boyfriend about 5 months ago, bad break up anyway, he lied to me a lot.

I usually use internet explorer, but instead I used google chrome today. When I went on it I noticed his email address was logged into gmail. I clicked on it and it sent me to the log in page. Yes I know awful but curiosity got the better of me and I remembered the password he used for everything.

I thought he might have changed it, but had a go. I was shocked to find he hadn't changed it and I had a look through his emails, I know dreadful. Strangely found out he had been cheating on me when I was with him. Still no excuse. Anyway as I was on it I was being careful not to open any unread emails, but accidentally opened one my accident.

He might notice that it has been read. I logged out straight away. Is there anyway he can find out this was me?

It was Gmail.

Please I know some of you will want to have a go at me, and say I deserve it,but could someone just answer the question?

As I need to be prepared in case he does find out.

Thanks
Updates
+1 y
Thanks for your answers guys, very helpful, and thank you for not having a go at me. I've been an idiot ha ha. Lesson learnt.
I logged into my ex boyfriends email account, is there any way he can find out?
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