Is this normal for IBS?

[Detonatress]

Hello. Can someone help me know if this is something to worry about, please? I am having a bunch of confusing symptoms and the doctors I've been to don't see anything unusual at my situation and the gastroenterologist at first gave me treatment for gastritis and minor hiatal hernia (treatment gave me gas and difficulty urinating so I stopped 2 weeks earlier than the 2 month treatment plan) and the second visit he gave me an abdominal ultrasound and just slapped the irritable bowel syndrome on it and prescribed medicine similar to what I've been prescribed before but that didn't help, they're just a different brand name.

My symptoms:
- started out as a roaming pain that went through limbs and neck, it became sharper during February until it disappeared in March.
- lost weight from 68kg (my usual constant weight no matter what I did) in February to 61kg this month. Even though I actually stopped doing push-ups and squats and instead just walk 1-3 hours a day since March (when I was already at 65kg). I had replaced the daily bowl of 1 Musli Cereal + milk, 5 kaiser roll bread and 2 baked chicken drumsticks or 2 pea bowls with 1 bowl of cornflakes cereal + vanilla soy milk, 4 gluten-free fiber bread and 2 duck legs or 2 bowls of lentils. Explained or unexplained weight loss?
- normal stool but sometimes has bright-white mucus, other times seems to have something like pinworms but I'm not sure, doctors just go by the one-time parasite test from stool that came out negative for parasites. (Last year in December I've been to a village where hygiene isn't very good, and another relative who was present there at the time has exact same symptoms I have)
- anal itching every few days during the evening.
- loud, cat meow-like bowel sounds coming from the colon's area at night while I'm in bed.
- constant feeling of having my left side held somewhat tightly below the rib, especially when taking deep breaths. (this started since December but it didn't seem as annoying at first).
- my hair seems to be falling more often than usual and turning very zig-zaggy curly.
- for about a week until now, pinkish-white patches on the edges of the tip of the tongue (may be from mouth breathing during sleep due to rhinitis that never got cured in spite of treatments).
- for about a week until now, throat pain (especially if I bend to pick something up, it hurts on the sides of the neck under the jaw joints)
- frequent extrasystoles (PVC) when I'm hungry or when I eat something that causes gas on the upper part of the abdomen. Bending causes the PVCs to multiply, but there are days when I completely avoid the PVCs if I don't get gas and don't end up hungry.

Are these normal things that might be happening with IBS? I've been to 2 gastroenterologists, got my heart checked twice too, nobody seems to think there's something odd about what I have, and all they say is "You're too young to worry about having any serious problems." Well, there are people who are kids/teenagers and have colon cancer so I'm not really feeling assured by that. I am 27 years old, female.