Blossom I totally understand why you did that because it's horrible when you realise someone you're dating is still using OD but that text has done several things. Firstly it shows that you've also been on POF, either looking for other men or checking up on MrSA (the latter of which may make him run for the hills). Secondly it puts him in a position of power because he knows that him being on there has rattled you. Thirdly, what can he reasonably reply to that? He can either deny it (unlikely), come up with an excuse such as he was looking at your profile again (sadly, this would most likely be a lie) or he could merely say 'Yes I have.', thus putting you on the back foot.
Remind me how long you've been seeing him?
If you sent that text just before you posted about it, that's not too long ago, so you can still recover it. Of course you can just wait and see if he replies then take it from there but if it was me I'd send another one saying something like 'I've been on there today too updating my profile and noticed you were online when I was having a browse. Not many men coming up to my exacting standards on there today though, unfortunately! x'.
That not only says that you are still looking around too and are taking active steps to do so, but that you have high standards that a man has to achieve to get you interested. The bit of humour shows you're being a bit tongue-in-cheek and the kiss shows that you are still interested in him, and because you're still interested in him, he must be coming up to your high standards.
Let us know what you decide and how you get on.