Phone battery replaced - draining as fast as before?!

[LittleRebelGirl]

I had my phone battery replaced this afternoon as it requires charging several times a day. I picked it up and the guy said the first 4 charges let it run down as low as you can without it switching off to prolong the battery life and avoid damage. He checked the charge percentage when I picked it up and said it was at 76% (which it was) and that should last me the rest of the day easily. Well, that was just before 3pm. It's just after 5 and it is on 23%! It is draining as fast as it was before the change! The company is a reputable company, been around for years in fixed premises. I have a receipt etc.
But is this normal? It doesn't sound normal? I go on holiday in 1 week and need it sorting before then.
Help!

What are you doing on your phone? If nothing or light texting then the phone drainage isn't normal. If you are playing Pokémon go or various other battery demanding games, then it's to be expected.

Have you made sure that you closed programs and turned off Bluetooth when not in use?

Is it an I phone? If so you can check what your battery life is, and it will tell u the percentage that the battery can charge up too

No, Samsung.
No games. Just Internet browsing.