Need advice!

So I’ve been sleeping with my “babydads” friend - yes using contraception.

I hardly see/speak to my babydad, he popped round the other day after last seeing his son on Xmas. So say he pops in every 6/7 months (and birthday and Christmas).

Little backstory we (me and bd) was sleeping together I got pregnant we was sleeping together the whole pregnancy (him saying he liked me and wanted to be with me etc) had the baby and then boom he gets with another girl (which I didn’t have a problem with and as they’ve been together over a year I’ve let him know it’s okay if he wants to introduce child to her whenever he next pops in if it’s gonna make seeing child more easier as I know some girls are uncomfortable with it)

I didn’t intend to sleep with his friend it just happened. I get bored and lonely no friends just my kid so I felt like I needed a bit of attention too if you get what I mean and his friend started messaging me after bumping into me on holiday. I told him I felt bad about bd cuz they know each other but did it anyway suppose I’m selfish in a way. He’s the only person I actually see. We’re not planning for nothing serious only slept with him twice but I just feel like I’m in the wrong (I probably am). It’s a secret and hopefully stays that way as my babydad would go mad at him.

But in terms of advice am I in the wrong and what should I say if my bd does find out?

They’ve been friends for 2 years so while I was pregnant