"How was..." requires a basic answer along the lines of simply "good"/"bad" or "well/"not well". "What was...like?" requires a much fuller account or description. Here are some examples where the distinction is clearer: "What's Jack like?" He's a nice guy. He's tall, good-looking, very friendly and sociable. "How's Jack?" He's fine. He had flu last week but he's all right now. "What's his car like?" It's a small blue sports car with a soft top and....etc "How's his car?" (maybe following a minor accident) It's OK. There are a few scratches and dents but nothing serious. In some cases, such as "How was your exam?" versus "What was your exam like?", the two questions amount to the same thing. You just want to know whether it was good or bad. The weekend question is similar, in that they may require the same answer ( "It was good. I did xx. How was yours?"). But be aware that these two questions are actually different. Spanish-speaking learners very often make the mistake of using "How...?" when they require details. Remember that "How" can only be used if you're asking for a simple assessment of something - if you need a description or full account, you should use "What... like?".

The first sentence is perfectly correct but I'm not sure about the second one. I mean, it is understandable and grammatically correct but it sound a bit unnatural to me. When you want to ask about the past weekend, you can also say "Did you have a good weekend?" or "Did you do anything fun over the weekend?"

"Is there someone wrong?" - I guess you wanted to write "is there anything wrong?" :)

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