You can differentiate love from lust when you take some things into consideration like
1) If you take away the physical appearance you are seeing or attracted too, do you still want to be with the person?? If Yes you are in Love
2) if you take away your desire for sex with the person will you still want to be with the person?? If yes you are in Love
3) Do you always look forward to spend quality time with the person without the thought of sex or another romantic benefit? If yes you are in Love
4) Do you think of spend the rest of your lie with the person?? If no you are in Lust.
Love and lust can be sometimes difficult to differentiate but if you check what I wrote above, you should be able to differentiate easily.
Love takes time and involves cherishing and caring for someone. There are many levels to this affection and it's pretty recognisable. Lust is physical attraction of a sexual nature. Sometimes, this physical attraction creates emotions, but they're fleeting and are inherently different to the warm emotions that love brings. More about the topic: https://www.mindbodygreen.com/0-12048/how-to-tell-if-its-love-or-just-lust.html