How do I say "I just went to the shops"? I'm specifically asking about the situation below:

Bob: we need more milk, I'll go to get some this evening
Blob: oh, I just went to the shops, but I forgot about milk 

I would tentatively translate Blob's reply as "啊，我刚刚去了一趟，忘了买牛奶". 

My questions is firstly: is the above translation good? And secondly, would it be possible or preferable to use 过 in this sentence? I know that when you're talking about a routine daily action you can say 过了, for example 我吃过了, so it occurred to me maybe I should say 啊，我刚去过商店了, but I'm not sure. I'm not clear how 过了 interacts with 刚 and I'm also not sure if "going to the shops" counts as a routine daily action? Or is there a less ambiguous guide I can follow for when to use 过了？

Many thanks in advance, 提前谢谢
刚=刚刚=刚才=just=just now
去=go
去过……了=went  

啊，我刚才去过商店了，但是忘了买牛奶
or
啊，我刚刚去过商店，但是忘记买牛奶了