Hi there, first time poster here who is just looking for some answers/help if possible please. I'm a 19 year old male who has always lived a pretty active and healthy lifestyle and in September moved into a house with several friends of mine. Everything was great until a couple of weeks ago, when I started to get a few minor but noticeable symptoms.

About two weeks ago, I noticed I had mild lower-left abdominal pain (from the bottom of the left-side of my ribs to just around my bowel area) and back ache in the same place on my back, sometimes spreading to my left side (between back and front). The pain/ache came and went throughout the day and wasn't particularly severe but troubled me as I'd not had substantial stomach ache in several years. As well as this, I was quite constipated for several days and as I have always believed myself to have a degree of IBS (Irritable Bowel Syndrome) I assumed that the two were linked.

At the same time as the stomach/back ache and constipation, I noticed I had a faint headache across the front and left side of my head, and occasionally had bouts of nausea. These two were only on/off throughout the day and weren't continuous but still disturbed me when they came on.

At the start of this week, my constipation ceased and now the stomach/back ache have almost completely gone (normal bowel movements have also resumed). However, the headaches are still present at certain times throughout the day and I still feel slightly nauseous several times each day. On top of these, my vision doesn't seem quite the same as normal; I wear contact lenses and although my sight itself doesn't seem any worse (I can still read, see the TV fine, see people etc) than usual, everything just seems a little... 'light-exposed', as if I've been staring at a bright sky and then looked away. This is only SLIGHTLY and I have even wondered if I am imagining this symptom simply to complement the headaches I've been having. Overall however, it is the headaches and nausea that have been bothering me this week and I've been reluctant to take painkillers due to concern with how long/persistant these symptoms will be.

The only other possible symptom to mention is a brief spell of ear ache I've had this week. Perhaps twice or three times this week, I've briefly felt slight ear ache in my left ear. This has only usually lasted for 15-20 minutes tops and is barely noticeable. I attributed this possibly to water (I swim twice a week) or perhaps ear war (I gain wax rather quickly).

With the headaches and nausea, I was concerned that I might perhaps be suffering from carbon monoxide poisoning (particularly as the house is quite old). However, the electronic CO alarm we have is not going off and none of my housemates have been having similar symptoms. What is intriguing however, is that my symptoms seem to go away/be less noticeable when I'm not in the house - I've been to university and out several times this week and on each occasion, felt much better only to feel nauseous/headachey soon after my return. Could this just be because when I'm sat in the house I notice the symptoms more?

As a bit of background about myself, I am relatively fit and healthy (5'8", 10 st 5 lbs) and go to the gym/swimming 2-3 times a week. I rarely smoke (the occasional cigarette on a night out is my limit) and I wouldn't say I drink any more than the usual student my age does. I have a heart murmur (diagnosed as a baby) and hayfever, but have never had any severe health problems. I know I might be coming across as a bit of a hypochondriac but I just want some peace of mind or advice with regard to these recent symptoms, even if it is just a bug/virus etc, especially as I'm usually a very healthy and well person.

Any advice/information would be hugely appreciated as I've been worried for much of the past 2 weeks. Thank you very much in advance!