Mocha Latte Protein Coffee

I have tried it at the suggestion of my weight loss doctor to try and get more protein in my diet. I'm really sensitive to non-sugar sweeteners, so I had to comb through the brands to find one that used sugar, had good reviews, and tested for lead - I landed on Naked. It's fine. The chocolate one that had instant coffee in it is better than the non-coffee ones, so I've bought instant coffee to add to the normal powder lol. I bought too much when I first ordered (I wanted to try 3 different products) and I'm doubting I'll ever get through it all before it goes bad... can pea protein go bad?