My question is, not necessarily targeted towards the interview on Monday, will it, in any way, hinder me, given that I have near negligible experience of Java or .Net and that I'm a fresher, in getting a job?

Yes and no.

If the job calls for front end experience and a company is deciding between one candidate with front end experience and one without (all else being equal), they will pick the more qualified candidate. However, rarely is "all else equal". Many companies don't hire people to fit a particular job description, they hire smart people that can fit a wide array of job descriptions. In other words, if the company thinks that you can learn new skills and technologies as required, they may hire you anyway. From the information you provided in your OP, it sounds like you are a smart individual who will have no trouble picking up front-end development technologies. However, many companies may not see it that way, especially because of the large differences between what you know and front-end development. Your job now is to convince them that you will be able to learn the new skills fast enough to make hiring you worthwhile. Getting more front-end experience will be incredibly helpful in doing this, but that should be obvious.

Best of luck.