Despite announcing a record quarterly profit of a whopping $18.4 Billion, Apple’s Q1 earnings call had a slightly negative tone as iPhone sales failed to grow significantly over last year’s numbers.

It started strongly, Apple CEO Tim Cook announcing that “our team delivered Apple’s biggest quarter ever, thanks to the world’s most innovative products and all-time record sales of iPhone, Apple Watch and Apple TV.” Pretty impressive – though a closer look at the numbers shows that both gross revenue and net income just barely exceeded the figures for this time last year. iPhone revenue in particular grew less than one percent.

After a long period of sustained growth, Wall Street seems concerned that this might signal a slowing of Apple’s high-speed profit train. It didn’t help that Cook admitted iPhone sales will likely decline next quarter over the same period last year. In fairness to Apple, this forecast is due to Q2 2015 making exceptional sales due to a lack of stock in Q1 2015. Jason Snell of MacWorld does a good job of summarizing the concerns:

“iPhone sales seem to have plateaued. Nobody’s saying they’re going to drop – the smartphone is basically one of the most popular product categories in existence – but if you’re focused purely on growth, this category may no longer be as exciting as it once was.”

Also noted in Apple’s press release is that around two-thirds of the quarter’s revenue came from an international audience, reflecting Apple’s growing presence around the world, especially in China where Apple clocked up record revenue. With that many sales coming from overseas, Cook was quick to highlight the fact that “macroeconomic conditions” and “economic headwinds” were partly to blame for the lack of growth. In English, that means that fluctuating and mainly unfavorable foreign currency rates affected the company’s profit margins around the world.

So we might see the ridiculous growth in iPhone sales grind to a halt in the coming months. At least until the iPhone 7 comes out this Fall, anyway. In the meantime it’s hard to feel too bad for Apple – remember, they still took in revenue of $75.9 billion in the last three months. Not too shabby.