I hate myself for being so "stupid"???

44 in Q is impressive. For me RC is the most a-pain-in-the ass from the verbal section. The most troubles come from ability to quickly comprehend the info (those texts from medicine or science) - a problem with all non native speakers I guess. Enhancing vocabulary might help, but how can you manage to learn much of it in a shirt term perspective? That is a question. I see no problems with answering the questions if you understand what is written there.
With lerning theory and everyday practicing you will easily master CR, this is a function of time imo, for one it takes longer, others need only a few examples, but in general, it turned out not as intimidating as I initially thought.
And SC. If you are a non-native speaker, this might be also time consuming for you but still doable. Just get the right preparation materials and study.