Thanks for your reply. I have no idea what was eating it. The damage was pretty minimal now I come to think of it and I feel like a real idiot for inflicting this much more visible damage on my baby. The side of the leaves looked like that had been eaten by a small pest and small holes were appearing on some of the leaves but I could never really visibly see the pests. The plant still looks healthy enough apart from the brown stains but some of the tips are starting to curl a bit and appear yellow/brown. Original bottom leaves are started to dry and fall off now but I've heard that usual. Thanks once again