I would go with the treat it like it didn't happen at first approach then later follow up with a little whisper in her ear while hugging from behind if you get the chance, "hey baby, sorry about the awkwardness yesterday, i was just a little stressed out and showed it in the wrong areas." give a simple peck and then move on. No need to dwell on it and stress out on it.
Second, I would refrain from the word "love" for a while if this is a new girlfriend. Some girls actually get freaked out by it.
If you tell her you were nervous, from that point on she will have a third eye to see if you're acting weird or not due to nervousness and start calling you out on it every time. That's what happened w/ me and my girlfriend but thank God we recovered from that mess. Don't DLV
Now this was posted 4 days ago so in those 4 days a lot could have happened. But I hope I was of help to you. Good luck!