Will baby be okay? Formula mix

So I made him a 5oz bottle like I usually do but he'd gone 4 hours instead of 3 so anyway he drained all his bottle and was still wanting more and really crying for it it had only being 40 mins since I made this so I rinsed the bottle and instead of wasting time making him a powder formula feed I used ready to use formula liquid he's had nearly 2 oz of it and is now content I'm now panicking I didn't use a fresh sterilised bottle... Will he be okay or have I contaminated his feed he's only 4 weeks I think he's having a growth spurt