^^ +1
Studying maths and implying that in real world examples are very different for many, Eg. Right now with me i have a group of buddies who had just mugged up how the problem was solved given the problem of pure math in the paper. However, given such same problem in the world of programming to generate a data-set for a graph their feet just wiggled off!!
this was my experience,
I hated math, even right now, but I am damn sure given a problem I may solve the query and make a program for the problem right in there within given frame of time.
Regarding OP's Query
HTML CSS are yet just the basics to structure and make the page look woow!! but the actual calculating efforts and genarating a webpage from a programming language dynamically thats where a developer meets a designer!!.
there are several programming languages keeping apart the the core logical part remains the same, I was from a biology background in my 11th and 12th, but it took no time for me to study maximum of the technologies,
Start with the Logic Chapter of Standard 12th
Start with any programming language, (Basically as all start with C/C++)
Initially with (data-types, loops, functions, classes, and many greek things for you)...
Look for SIMILARITIES in other languages when you study them, AFTER completing the first one,
Ask the question does the language offers any other features...
This is how I completed my carrier in programming for last three years
1. C, Logic (Done) + Statistical math ie Basics plus, minus
2. C++, *Graphics under C(Not required), Java, and SQL-database(the parts of applications where our data resides)
3. Event driven programming:
languages namely:
Visual Basic .NET, C#.NET, Java Swing <3 VB.net for events
Web Programming:
HTML5 CSS3,
JavaScript JS
If you need to learn web programming, you can easily learn within a course of a week, if you know the fundamentals of any above heres a list
PHP(Hypertext Preprocessor),
JSP(Java server Pages) + JSTL + Servlet
ASP.NET (Active Server Pages)
Ajax / JQuery
There are free Courses lectures available
CS50 -- > Core Logic
CSE75 -- > PHP + Ajax Web App Dev
No for java web dev

Study on your own by reffering Head first Java > Head First JSP + Servlet