N.H.
Good Morning L.,
I have mentioned this to quite a few nursing moms, and I can only assume you have something working well for you with the bottle. I have recommended the NUK nipple, it is shaped most like you and will not confuse your baby when switching from breast to bottle. But you didn't mention any problems with this, sorry.
With being gone for 3 days, I know you will probably be busy, and unable to pump as often as your baby nurses when you are together.
You probably shouldn't have a problem with cutting back for a couple days, to maybe 3 or 4 pumpings throughout the day, when you can.
When you get back to your baby, you will notice a reduction in milk production, but it shouldn't take long to rebuild. Just get back to nursing like normal, a little more often, if needed, to get back up to normal production level. This should take less than a week or so.
As long as you pump a couple times a day, you will not lose your milk, it will just slow down production, until you get back onto a regular schedule.
It takes longer than 3 days for milk production to stop, it only slows down. Just remember to pump a couple times a day to keep it going strong, then back to a normal nursing schedule will bring full production back to normal.
Good luck