I am feeling those things right now as well. Panic attacks can happen when you can't pin point an exact cause. If you read about panic disorder online, it will give you a lot of information; and we have resources here on HW as well.
Drining ice cold water helps a lot.
Try to take some deep breaths. Beathe in through your nose, slowly (count to 5 or 10) and then hold it for a few seconds, and then slowly again counting to 5 or 10 as you exhale through your mouth. Deep breathing should come from your belly, not your chest. So you can try this laying down watching your tummy fill with air and then flatten again....
Grounding techniques are helpful too. Try sitting in a chair, couch....with your feet touching the floor. Focus that your feet are touching the floor, that you are sitting on something....Grounding techniques help a lot when you feel dizzy and weak.
I also had someone coach me through a panic attack once by them telling me to go wash my face with soap and warm water and then to call him back. I felt a lot better after washing my face....I still use that one. It doesn't always work, but it's worth a try.
I really sugggest the breathing and grouding.....I will try to look up more techniques online today...
Bipolar II, Anxiety/Panic Disorder
Clonazepam .5mg as needed for panic attacks
---temporarily off Lamictal----