You might want to check out the nearest Archie's for this. Or if you want specific ideas, you can give her trendy bag from H&M, cute top from Zara, a make-up pallette she has been eyeing from the nearest Nykaa store or maybe even a combination of all of these!
I guess a watch would be a nice gift
You can also gift customised chocolates for your girlfriend with your photos.
Checkout - De'chocomeraki they have lot of options.
First make ur mind what she likes n all .. Its most important .. Or plan u wanna give something worth money she can use or loads of love with a key or token of love for her ..
As a layman i can suggest u .. Get something customized .. See the gift options on woodgeekstore.com , shopvalley.com , Archies ... Etc