Seeking Advice

So my partner and I have been together for a year, last year when we first met we both were in ‘entanglements’ I guess you could say. Neither of us were in serious relationships with other people but we had people in our lives we were intimate with.

Once we met and I knew we had a connection I ended mine as it was the right thing to do, his went on a month longer.

Over the last year on and off this women has popped back up either through emails or messages with general chat.

Today though I was on our computer and an email popped up from her and I read it. Wrong as that may be it happened and the email chain was from a few days but this time he had started the conversations.

It was a bit flirty and made reference to there past sexual relationship.

I confronted him immediately and he blocked the Gmail from the computer so I could no longer see the emails and said that he was just curious about what she was up to and wanted to find out what was going on with her. So he had contacted her

Normally I would say that’s no problem as we have had a good relationship but he hid it from me purposefully and while he says he has zero interest in this women he went out of his way to speak to her, to the point he went through old call logs on his phone to get her number to message

I am 7 weeks pregnant and there’s been a few issues over the past couple of weeks with pain and bleeding so it’s caused so upset.

My question is am I overreacting to what could be a simple thing and while he may flirt (as I do on occasion with men) is it enough to really consider ending our relationship, which is how I currently feel 😕