Is this normal?

I've been having back spasms for several days now, even though I'm 55 pounds lighter and never had back problems when I was heavier. For me, I think it's a change in the weather or the fact I haven't exercised in a week.

I hope you figure it out and get some relief soon! :flowerforyou:

One of the best things you can do for core exercises is planks -- they can be done almost anywhere and don't require any special equipment or expensive gym membership!

For nights: pillow or rolled up towel beneath your knees (if you lay on your back), or between your knees (if you lay on your side). (Some chiropractors have a neat pillow-style support that is an hourglass shape so it doesn't slip out when you have it between your legs on your side.)
For work: get a lumbar support for your chair (they're curved outward and will support the natural curve of your spine.
For all day: posture support (something like this: http://www.proline-sports.co.uk/acatalog/proline_posture_FULLY_ADJUSTABLE_DELUXE_POSTURE_CORRECTIVE_BRACE_Proline_UK.html -- I have a lumbar support and posture corrector that I use when my back starts to bug me)
Exercises: crunches, not full sit-ups, invest in a workout ball (the big ones that you can sit on)... also, work on doing superman extensions (lay on your stomach and use your back muscles to pull your torso and legs up off the ground, but go easy!)
Stretches: lay on your back, pull each knee up (separately) and hold... then together and hold. On your back, pull one knee up and slowly lean it over to the opposite side, repeat with the other knee.
For pain: anti-inflammatory, like ibuprofen, etc. (within reason! especially good to take some before you go to bed, to relax the muscles and allow proper alignment and healing while in a prone state.)

Bad posture impacts a lot of things, and people who work at computers often have some issue. The above is what my doctor recommended to me,

As for the chest pain, throat tightness... you may have some asthma, but that's something you need to talk to a doctor about. If it worries you, it's definitely worth talking to a doctor for!

Further edit: I should also mention that my pain is in the mid/upper part of my back.

A lot of upper and middle back pain can be from your head being forward or repetitive motion especially with your arms lifted. I have no idea what you do, but you mentioned the computer, and a lot of people on computers have their heads thrust forward (what we call military neck). If you don't have your spine aligned correctly when you are sitting or standing (you mentioned your posture), the muscles have to take over the work the bones are designed to do. Think about your body mechanics, when poor, they can be very destructive. The fact that you refer to your being "out of shape" could also be a clue that you may be doing too much, too quickly. Stretching is incredibly important so your muscles don't tighten up. Hope you are feeling better soon, or you should probably get to a chiropractor, licensed massage therapist, accupuncturist or DO. Best of luck! :flowerforyou:

I'd do some core work but I'd certainly visit the doctor first and get checked over! X

Make an appointment to see a chiropractor ASAP. They are really not that expensive, usually around $35, funny thing is, using insurance usually costs more than out of pocket. They can help you figure out exactly what's wrong. I would deffinately go there over a family doc for back pain, because usually the only thing a family doc reccomends is pills or surgery, they have no clue how to get to the root of the problem. A chiropractor actually has more years in med school than a doc, atleast here in NC. It's like I tell people, if your transmission goes out in a car, you can take it to a regular mechanic, who would probably suggest either getting a new one or just rebuilding yours, but if you take it to a transmission specialist they can fix it better, and most times cheaper.

go to the doctor and get checked. my hubby suffered from back aches and pains for years finally dragged him to the gp and he has advanced degenerative disc disease in 3 places! and because he left it so long there isnt much they can do for him now. never risk your back, it might be nothing, or it might not

As far as the chest pain and throat tightness, my first thought was asthma as well. There is such a thing as exercise-induced asthma that is otherwise not bothersome but affects people only when they exercise/exert themselves. Definitely something to talk with a doc about.